[Supanode](https://supanode.xyz/)The terms behind the stack. # The terms behind the stack. Definitions for reading RPC documentation, comparing data interfaces and building reliable clients. Network labels provide context; this glossary is not a service catalog. Find a termClear 76 terms [A](https://supanode.xyz/glossary#abi)[B](https://supanode.xyz/glossary#base-fee)[C](https://supanode.xyz/glossary#chain-id)[E](https://supanode.xyz/glossary#energy-and-bandwidth)[F](https://supanode.xyz/glossary#finality)[G](https://supanode.xyz/glossary#gas)[H](https://supanode.xyz/glossary#retention-window)[J](https://supanode.xyz/glossary#jito-bundles)[K](https://supanode.xyz/glossary#kol-wallet)[L](https://supanode.xyz/glossary#lamport)[M](https://supanode.xyz/glossary#masterchain)[N](https://supanode.xyz/glossary#sync-status)[P](https://supanode.xyz/glossary#pagination-cursor)[R](https://supanode.xyz/glossary#rate-limit)[S](https://supanode.xyz/glossary#sandwich-attack)[T](https://supanode.xyz/glossary#transaction-receipt)[W](https://supanode.xyz/glossary#pubsub-subscription)[Y](https://supanode.xyz/glossary#yellowstone-grpc) ## ABI (application binary interface) EVM An ABI describes how contract calls, return values and events are encoded into bytes. A client needs the correct interface to turn a function name and typed arguments into calldata, or to interpret a returned value. The same bytes can be decoded incorrectly when the ABI does not match the deployed contract. [Event log](https://supanode.xyz/glossary#event-log)[Event topic](https://supanode.xyz/glossary#event-topic)[Raw (signed) transaction](https://supanode.xyz/glossary#raw-transaction)[Solidity ABI specification](https://docs.soliditylang.org/en/latest/abi-spec.html) ## ADNL (TON) TON reference ADNL is the networking layer TON uses to identify peers and exchange messages. Lite clients use its TCP form to communicate with liteservers. An ADNL endpoint is a different protocol from an HTTP JSON-RPC endpoint, so substituting one URL for the other does not create compatibility. [Liteserver (TON)](https://supanode.xyz/glossary#liteserver)[Workchain (TON)](https://supanode.xyz/glossary#workchain)[TON Docs: ADNL protocol](https://docs.ton.org/v3/documentation/network/protocols/adnl/overview) ## Alpenglow Solana Alpenglow is a Solana consensus design developed by Anza to change how validators vote and finalize blocks. Its Votor component handles consensus, while the research design also describes Rotor for data dissemination. Published simulation targets are not measurements of an application's end-to-end latency. Activation dates, client versions and operating parameters require a separate current network check. [Finality](https://supanode.xyz/glossary#finality)[Commitment level](https://supanode.xyz/glossary#commitment-level)[Shred (Solana)](https://supanode.xyz/glossary#shred)[Anza: Alpenglow consensus design](https://www.anza.xyz/blog/alpenglow-a-new-consensus-for-solana) ## Arbitrum Orbit chain (Arbitrum chain) Arbitrum / Robinhood An Arbitrum chain is a blockchain built with the Arbitrum technology stack; Orbit is the earlier name for this deployment framework. Its execution, data availability and settlement configuration depend on the chain. Applications should check the particular chain's documentation instead of assuming every Arbitrum deployment has Ethereum's block timing and finality behavior. [Layer 2 rollup](https://supanode.xyz/glossary#l2-rollup)[Sequencer (L2)](https://supanode.xyz/glossary#sequencer)[Chain ID](https://supanode.xyz/glossary#chain-id)[Arbitrum docs: glossary (Arbitrum chain)](https://docs.arbitrum.io/intro/glossary)[Arbitrum docs: overview of Arbitrum chains](https://docs.arbitrum.io/launch-arbitrum-chain/overview/introduction) ## Archive node Cross-network An archive node keeps historical state that a pruned node may discard. Historical state means values such as an account balance or contract storage at an earlier block. It differs from merely retaining old transaction records. The oldest queryable state depends on the node's storage mode and the API exposed. [History retention window](https://supanode.xyz/glossary#retention-window)[State root](https://supanode.xyz/glossary#state-root)[Transaction trace](https://supanode.xyz/glossary#trace)[Ethereum.org: nodes and clients (archive node)](https://ethereum.org/developers/docs/nodes-and-clients/)[Geth command-line options (--gcmode)](https://geth.ethereum.org/docs/fundamentals/command-line-options) ## Associated token account (ATA) Solana An associated token account is the conventionally derived token account for a wallet, token mint and token program. The wallet address alone is not its SPL token balance account. A wallet may also own other token accounts for the same mint; the ATA is the canonical address derived by the Associated Token Account program. [Program derived address (PDA)](https://supanode.xyz/glossary#program-derived-address)[Solana RPC](https://supanode.xyz/glossary#solana-rpc)[SPL Associated Token Account program](https://www.solana-program.com/docs/associated-token-account)[Solana docs: tokens](https://solana.com/docs/tokens) ## Base fee (EIP-1559) EVM Under EIP-1559, the base fee is the protocol-calculated gas price component that applies to a block. On Ethereum this component is burned, and a sender separately sets a maximum total gas price and a priority fee cap. Other EVM networks can change fee rules, so Ethereum's fee breakdown is not a universal billing formula. [Gas](https://supanode.xyz/glossary#gas)[Priority fee](https://supanode.xyz/glossary#priority-fee)[Wei and gwei](https://supanode.xyz/glossary#wei-and-gwei)[EIP-1559: fee market change](https://eips.ethereum.org/EIPS/eip-1559)[Ethereum.org: gas and fees](https://ethereum.org/developers/docs/gas/) ## Block height Cross-network Block height locates a produced block in the chain's sequence of blocks. Solana reports both heights and slots. A skipped slot advances the slot count without producing another block, so the two values cannot be substituted. For a recent blockhash, compare expiry against lastValidBlockHeight rather than a slot number. [Slot](https://supanode.xyz/glossary#slot)[Recent blockhash (Solana)](https://supanode.xyz/glossary#blockhash)[Solana RPC: getBlockHeight](https://solana.com/docs/rpc/http/getblockheight)[Solana RPC: latest blockhash expiry](https://solana.com/docs/rpc/http/getlatestblockhash) ## Block tag EVM A block tag is a named choice of blockchain state used in an RPC request, such as latest, pending, safe or finalized. The tag chooses when to evaluate a balance, call or other state query. Support and meaning depend on the network and method. Two calls using latest can observe different blocks if the head advances between them. [Finality](https://supanode.xyz/glossary#finality)[Transaction receipt](https://supanode.xyz/glossary#transaction-receipt)[JSON-RPC](https://supanode.xyz/glossary#json-rpc)[Ethereum JSON-RPC API: the default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block) ## Bonding Curve Solana / DeFi A bonding curve is a contract pricing rule that calculates a trade's price from variables such as supply or reserves. Launchpads can use it before moving a token into a liquidity pool. The pricing equation, completion rule and destination pool belong to the particular program; a fixed market-cap threshold or migration venue should not be assumed for every token. [Slippage](https://supanode.xyz/glossary#slippage)[Jupiter Aggregator](https://supanode.xyz/glossary#jupiter-aggregator)[Pump official program documentation](https://github.com/pump-fun/pump-public-docs/blob/main/docs/PUMP_PROGRAM_README.md) ## Bounceable address (TON) TON reference A bounceable TON address is a user-friendly encoding that signals a preference for bounceable messages. The bounce flag can return remaining message value when delivery or execution fails under TON's rules. Bounceable and non-bounceable encodings can identify the same account. Wallet handling and account initialization still matter when sending funds. [Workchain (TON)](https://supanode.xyz/glossary#workchain)[Logical time (TON)](https://supanode.xyz/glossary#logical-time)[TON Docs: address formats](https://docs.ton.org/v3/documentation/smart-contracts/addresses/address-formats) ## Chain ID EVM A chain ID is the numeric identity used by EVM transaction signing and exposed by eth\_chainId. Including the ID in supported signature formats prevents the same signed transaction from being accepted on a different chain with a different ID. Read the endpoint's chain ID before signing; a familiar address format does not identify the network. [Raw (signed) transaction](https://supanode.xyz/glossary#raw-transaction)[Nonce (account nonce)](https://supanode.xyz/glossary#nonce)[EIP-155: simple replay attack protection](https://eips.ethereum.org/EIPS/eip-155)[EIP-695: eth\_chainId](https://eips.ethereum.org/EIPS/eip-695) ## Chain reorganization (reorg) Cross-network A reorganization occurs when a node adopts a different branch as its canonical chain. Recent transactions or logs can disappear from the accepted branch and later appear elsewhere. Consumers of non-final data need a way to undo provisional records. A WebSocket notification alone does not prove that an event is final. [Fork](https://supanode.xyz/glossary#fork)[Finality](https://supanode.xyz/glossary#finality)[WebSocket subscription](https://supanode.xyz/glossary#pubsub-subscription)[Geth: real-time events (pub/sub)](https://geth.ethereum.org/docs/interacting-with-geth/rpc/pubsub) ## Commitment level Solana Commitment selects the degree of confirmation required for a Solana read or subscription. Processed follows a node's observed execution; confirmed requires the documented voting threshold; finalized uses the most settled state exposed by the RPC. Use a consistent commitment across related reads and transaction checks to reduce apparent contradictions. [Finality](https://supanode.xyz/glossary#finality)[Fork](https://supanode.xyz/glossary#fork)[Solana RPC](https://supanode.xyz/glossary#solana-rpc)[Solana RPC: configuring state commitment](https://solana.com/docs/rpc) ## Compute unit (Solana) Solana A compute unit measures execution work charged by Solana's runtime. Transactions have a compute budget, and a program can fail when it exhausts that budget. The requested unit limit and unit price also affect prioritization fees. An RPC provider's request credits are a separate accounting system. [Priority fee](https://supanode.xyz/glossary#priority-fee)[Preflight simulation (Solana)](https://supanode.xyz/glossary#preflight)[Solana: transaction compute and fees](https://solana.com/docs/core/fees) ## Copy Trading Trading concept Copy trading automates trades based on activity observed in another account or a chosen strategy. A follower still chooses sizing, allowed assets, execution route and failure behavior. Its fill can differ from the observed trade because detection, liquidity, fees and transaction ordering change before execution. Blockchain data delivery is one component of the application. [KOL Wallet](https://supanode.xyz/glossary#kol-wallet)[Slippage](https://supanode.xyz/glossary#slippage)[Solana RPC](https://supanode.xyz/glossary#solana-rpc)[Solana RPC: transaction observation](https://solana.com/docs/rpc/http/gettransaction)[Jupiter swap routing](https://developers.jup.ag/docs/swap/v1/get-quote) ## Energy and bandwidth (TRON) TRON reference TRON meters transaction bytes with bandwidth and smart-contract execution with energy. Accounts can obtain resources through the network's staking and delegation mechanisms; insufficient resources can require burning TRX under protocol rules. Consult the transaction receipt for actual consumption rather than inferring the fee from transaction count alone. [TRC-20](https://supanode.xyz/glossary#trc-20)[Super representative (TRON)](https://supanode.xyz/glossary#super-representative)[TRON Developer Hub: resource model](https://developers.tron.network/docs/resource-model) ## EOA vs contract account EVM An externally owned account authorizes transactions with a key; a contract account executes deployed code. An EOA traditionally initiates a top-level transaction, while a contract responds through execution. Modern authorization and account-abstraction mechanisms add behavior to this model, so the presence of code is not always enough to infer how an account is controlled. [Nonce (account nonce)](https://supanode.xyz/glossary#nonce)[ABI (application binary interface)](https://supanode.xyz/glossary#abi)[Raw (signed) transaction](https://supanode.xyz/glossary#raw-transaction)[Ethereum.org: accounts](https://ethereum.org/developers/docs/accounts/) ## Epoch (Solana) Solana An epoch groups slots into a protocol scheduling period. Leader scheduling and staking-related changes use epoch boundaries. Query getEpochInfo and getEpochSchedule when software needs the current position or schedule, rather than converting a fixed number of wall-clock hours into an assumed epoch number. [Slot](https://supanode.xyz/glossary#slot)[Leader and leader schedule (Solana)](https://supanode.xyz/glossary#leader)[Solana RPC: epoch information](https://solana.com/docs/rpc/http/getepochinfo) ## Event log EVM An event log is structured output emitted by contract execution and attached to a transaction receipt. Its contract address, topics and data let applications select and decode events. A token transfer event describes execution output; it is not a standalone transaction. Indexers should retain the block identity so provisional logs can be corrected after a reorganization. [Event topic](https://supanode.xyz/glossary#event-topic)[ABI (application binary interface)](https://supanode.xyz/glossary#abi)[Transaction receipt](https://supanode.xyz/glossary#transaction-receipt)[Solidity docs: events](https://docs.soliditylang.org/en/latest/contracts.html#events)[EIP-20: token standard (Transfer event)](https://eips.ethereum.org/EIPS/eip-20) ## Event topic EVM A topic is a 32-byte indexed field in an EVM event log. For a non-anonymous event, the first topic identifies the event signature; additional topics encode or hash indexed arguments. Non-indexed arguments live in the data field. Correct filtering therefore requires the event ABI and the argument's indexing rules. [Event log](https://supanode.xyz/glossary#event-log)[ABI (application binary interface)](https://supanode.xyz/glossary#abi)[Solidity docs: events](https://docs.soliditylang.org/en/latest/contracts.html#events)[Solidity ABI specification: events](https://docs.soliditylang.org/en/latest/abi-spec.html#events) ## Finality Cross-network Finality is the consensus assurance that accepted history will remain canonical under the protocol's assumptions. A fast acknowledgement, an observed execution and a finalized block represent different stages. Networks define those stages differently; rollups can also distinguish sequencer acceptance from settlement on a parent chain. Choose the stage appropriate to the application's consequence. [Commitment level](https://supanode.xyz/glossary#commitment-level)[Chain reorganization (reorg)](https://supanode.xyz/glossary#reorg)[Layer 2 rollup](https://supanode.xyz/glossary#l2-rollup)[Ethereum: proof of stake finality](https://ethereum.org/developers/docs/consensus-mechanisms/pos/)[Robinhood Chain: transaction finality](https://docs.robinhood.com/chain/transaction-finality) ## Fork Cross-network A fork is a branch of ledger history that diverges from another branch sharing the same past. Nodes can temporarily observe competing branches before consensus selects accepted history. Here the term describes ledger branches, not a software repository copy or a separately governed protocol split. A change of canonical branch is a reorganization. [Chain reorganization (reorg)](https://supanode.xyz/glossary#reorg)[Finality](https://supanode.xyz/glossary#finality)[Solana docs: terminology](https://solana.com/docs/references/terminology)[Solana docs: retrying transactions](https://solana.com/docs/advanced/retry) ## Gas EVM Gas measures the computational and storage work of EVM execution. The gas limit caps the work a transaction is allowed to consume; the gas price states the cost per unit. Gas used multiplied by effective gas price gives an execution fee, while some networks add other fee components. [Base fee (EIP-1559)](https://supanode.xyz/glossary#base-fee)[Priority fee](https://supanode.xyz/glossary#priority-fee)[Transaction receipt](https://supanode.xyz/glossary#transaction-receipt)[Ethereum.org: gas and fees](https://ethereum.org/developers/docs/gas/)[EIP-1559: fee market change](https://eips.ethereum.org/EIPS/eip-1559) ## Geyser Plugin Solana Geyser is an Agave validator plugin interface for exporting account, transaction, block and slot notifications to external systems. A plugin can feed a database, indexer or streaming server. Geyser itself is an in-process interface rather than a client-facing transport protocol; Yellowstone adds a particular gRPC service on top of this data path. [Yellowstone gRPC](https://supanode.xyz/glossary#yellowstone-grpc)[Shred (Solana)](https://supanode.xyz/glossary#shred)[Agave Geyser plugin interface](https://docs.anza.xyz/validator/geyser/) ## History retention window Cross-network A retention window describes how far back a particular system still stores and serves a category of data. Blocks, transaction metadata, event indexes and historical account state can have different windows on the same service. Retention is a storage property. Replay is a delivery feature that may expose a smaller portion of retained data. [Archive node](https://supanode.xyz/glossary#archive-node)[Replay](https://supanode.xyz/glossary#replay)[Solana RPC: getFirstAvailableBlock](https://solana.com/docs/rpc/http/getfirstavailableblock)[TON Docs: running a liteserver](https://docs.ton.org/v3/guidelines/nodes/running-nodes/liteserver-node) ## Horizon (Stellar) Stellar reference Horizon is Stellar's HTTP API for indexed network data, including accounts, transactions and operations. It supports resources and pagination designed for applications, and some endpoints support event streaming. Stellar RPC provides another interface, including smart-contract workflows. Choose the API by the data and operation needed rather than treating the two services as interchangeable. [Soroban and Stellar RPC](https://supanode.xyz/glossary#soroban)[Server-Sent Events (SSE)](https://supanode.xyz/glossary#server-sent-events)[Pagination cursor](https://supanode.xyz/glossary#pagination-cursor)[Stellar docs: Horizon API](https://developers.stellar.org/docs/data/apis/horizon)[Horizon API: streaming](https://developers.stellar.org/docs/data/apis/horizon/api-reference/structure/streaming) ## Jito Bundles Solana / Jito A Jito bundle groups signed transactions for ordered, atomic execution through Jito's Block Engine submission path. Under documented limits, the transactions execute together within one slot or the bundle does not execute as that bundle. Tips participate in selection. A returned bundle ID is a submission receipt, so check landing status separately and do not assume universal protection from MEV. [Priority fee](https://supanode.xyz/glossary#priority-fee)[MEV on Solana](https://supanode.xyz/glossary#mev-solana)[Raw (signed) transaction](https://supanode.xyz/glossary#raw-transaction)[Jito: low latency transaction send and bundles](https://docs.jito.wtf/lowlatencytxnsend/) ## JSON-RPC General protocol JSON-RPC defines a JSON message format for invoking named methods and receiving results or structured errors. A request normally includes a protocol version, method, parameters and an identifier used to match the response. The format does not define blockchain methods, transport security, history depth or request limits; those belong to the API and service. [Solana RPC](https://supanode.xyz/glossary#solana-rpc)[Rate limit (HTTP 429)](https://supanode.xyz/glossary#rate-limit)[JSON-RPC 2.0 specification](https://www.jsonrpc.org/specification) ## Jupiter Aggregator Solana / Jupiter Jupiter provides swap routing that can select liquidity paths across supported Solana trading venues. A quote specifies expected output and route information for particular inputs and parameters. It can become stale before execution. The routing engine, supported venues and API versions evolve, so integrations should use the current official interface rather than assume every venue is always included. [Slippage](https://supanode.xyz/glossary#slippage)[Bonding Curve](https://supanode.xyz/glossary#bonding-curve)[Solana RPC](https://supanode.xyz/glossary#solana-rpc)[Jupiter: swap routing and quotes](https://developers.jup.ag/docs/swap/v1/get-quote) ## KOL Wallet Solana / trading reference KOL wallet is an informal label for an address associated with a public trader, influencer or a community-tracked identity. The blockchain exposes transactions for an address, not a verified real-world identity. An attribution label and a performance ranking are separate evidence. Check how a source establishes ownership before building copy-trading rules around a name. [Copy Trading](https://supanode.xyz/glossary#copy-trading)[Realized vs Unrealized PnL](https://supanode.xyz/glossary#pnl-realized-vs-unrealized)[Solana: signatures for a specified address](https://solana.com/docs/rpc/http/getsignaturesforaddress)[Solana: account model](https://solana.com/docs/core/accounts) ## Lamport Solana A lamport is the smallest native SOL denomination: one billion lamports equal one SOL. RPC balance fields use integer lamports. Keep the integer representation for accounting and convert only for display; floating-point rounding can change a small amount or a fee calculation. [Rent exemption (Solana)](https://supanode.xyz/glossary#rent-exemption)[Solana RPC](https://supanode.xyz/glossary#solana-rpc)[Solana RPC: balances in lamports](https://solana.com/docs/rpc/http/getbalance) ## Layer 2 rollup EVM / rollups A rollup executes transactions outside its settlement layer and uses that layer to anchor and verify its state according to the rollup design. Ordering, data publication, proof or dispute procedures, and withdrawal completion can occur at different stages. A transaction appearing in the rollup's RPC does not by itself mean its result has completed every settlement step. [Sequencer (L2)](https://supanode.xyz/glossary#sequencer)[Finality](https://supanode.xyz/glossary#finality)[Arbitrum Orbit chain (Arbitrum chain)](https://supanode.xyz/glossary#arbitrum-orbit)[Ethereum.org: scaling](https://ethereum.org/developers/docs/scaling/) ## Leader and leader schedule (Solana) Solana A leader is the validator assigned to produce entries for a particular slot; a leader schedule maps those assignments. The assignment helps transaction-delivery systems identify the relevant validators. An assigned slot is not a promise that a block will be produced. Query the schedule when needed instead of deriving the next leader from a single observed block. [Slot](https://supanode.xyz/glossary#slot)[Epoch (Solana)](https://supanode.xyz/glossary#epoch)[Shred (Solana)](https://supanode.xyz/glossary#shred)[Solana RPC: leader schedule](https://solana.com/docs/rpc/http/getleaderschedule) ## Ledger (Stellar) Stellar reference A Stellar ledger is an agreed snapshot of network state together with the result of the transactions applied at that step. Ledgers have sequence numbers and hashes. The ledger sequence identifies a network-wide state boundary, while an account's transaction sequence number orders that account's submissions. These two counters serve different purposes. [Sequence number (Stellar)](https://supanode.xyz/glossary#sequence-number-stellar)[Finality](https://supanode.xyz/glossary#finality)[Stellar docs: glossary](https://developers.stellar.org/docs/learn/glossary)[Stellar RPC: getEvents](https://developers.stellar.org/docs/data/apis/rpc/api-reference/methods/getEvents) ## Liteserver (TON) TON reference A liteserver is a TON node interface that answers lite-client queries for chain data and proofs. Clients communicate through TON's ADNL protocol. Access to an old block depends on the serving node's available history, so a reachable liteserver is not automatically an archive source. [ADNL (TON)](https://supanode.xyz/glossary#adnl)[History retention window](https://supanode.xyz/glossary#retention-window)[Masterchain (TON)](https://supanode.xyz/glossary#masterchain)[TON Docs: running a liteserver](https://docs.ton.org/v3/guidelines/nodes/running-nodes/liteserver-node)[TON Docs: ADNL protocol](https://docs.ton.org/v3/documentation/network/protocols/adnl/overview) ## Logical time (TON) TON reference Logical time is TON's ordering counter used in messages and transactions. It expresses causal order without being a Unix timestamp. APIs can use an account transaction's logical time together with its hash to identify or paginate history. Compare it within the documented context instead of converting it to seconds. [Pagination cursor](https://supanode.xyz/glossary#pagination-cursor)[Workchain (TON)](https://supanode.xyz/glossary#workchain)[TON Docs: messages and transactions](https://docs.ton.org/v3/documentation/smart-contracts/message-management/messages-and-transactions) ## Masterchain (TON) TON reference The masterchain coordinates TON's shared network state, configuration and information about the other chains. It is identified by workchain ID -1. It does not hold every application's full transaction history; application activity is also recorded in workchains and their shards. Queries must use the correct chain context. [Workchain (TON)](https://supanode.xyz/glossary#workchain)[ADNL (TON)](https://supanode.xyz/glossary#adnl)[TON: chain domains and masterchain](https://docs.ton.org/foundations/addresses/overview) ## Mempool (transaction pool) EVM reference A mempool is a node's local collection of pending transactions waiting for possible inclusion. Different nodes can hold different pending sets, and a pending transaction can be replaced or dropped. Solana's transaction forwarding does not use the same shared public transaction-pool model, so EVM mempool assumptions should not be applied to Solana feeds. [Nonce (account nonce)](https://supanode.xyz/glossary#nonce)[Raw (signed) transaction](https://supanode.xyz/glossary#raw-transaction)[Leader and leader schedule (Solana)](https://supanode.xyz/glossary#leader)[Geth txpool namespace](https://geth.ethereum.org/docs/interacting-with-geth/rpc/ns-txpool)[Solana docs: retrying transactions (no mempool)](https://solana.com/docs/advanced/retry) ## Merkle proof (eth\_getProof) EVM A Merkle proof supplies the hashed tree path needed to verify an account or storage value against a trusted state root. With eth\_getProof, an application can verify selected state without downloading the entire state tree. The proof is meaningful only when its root belongs to a block the application trusts. [State root](https://supanode.xyz/glossary#state-root)[Archive node](https://supanode.xyz/glossary#archive-node)[EIP-1186: eth\_getProof](https://eips.ethereum.org/EIPS/eip-1186) ## MEV on Solana Solana / trading Maximal extractable value is value obtainable by influencing transaction inclusion, exclusion or ordering; on Solana this can include arbitrage and other ordering strategies. The submission path and validator behavior affect exposure. Jito bundles are one execution mechanism, not a definition of all Solana MEV. Observing data earlier does not guarantee a profitable trade or immunity from competing transactions. [Jito Bundles](https://supanode.xyz/glossary#jito-bundles)[Sandwich Attack](https://supanode.xyz/glossary#sandwich-attack)[Leader and leader schedule (Solana)](https://supanode.xyz/glossary#leader)[Jito: Block Engine and bundle auctions](https://docs.jito.wtf/lowlatencytxnsend/)[Ethereum: MEV concepts](https://ethereum.org/developers/docs/mev/) ## Muxed account (Stellar) Stellar reference A muxed account combines a Stellar account address with an integer identifier used to distinguish recipients sharing that account. The M-prefixed address resolves to the underlying G-prefixed account; it does not create another ledger account or balance. Confirm that a destination supports muxed addresses before using them for routing. [Ledger (Stellar)](https://supanode.xyz/glossary#ledger-stellar)[Sequence number (Stellar)](https://supanode.xyz/glossary#sequence-number-stellar)[Stellar docs: pooled accounts, muxed accounts and memos](https://developers.stellar.org/docs/build/guides/transactions/pooled-accounts-muxed-accounts-memos) ## Node sync status Cross-network Sync status describes whether a node is still catching up with the network and can also report its progress. An HTTP response only proves that the service answered. Compare head position or the network's health method when fresh state matters. Sync status does not establish archive depth or guarantee the latency of a particular request. [History retention window](https://supanode.xyz/glossary#retention-window)[Block height](https://supanode.xyz/glossary#block-height)[Solana RPC](https://supanode.xyz/glossary#solana-rpc)[Ethereum JSON-RPC API: eth\_syncing](https://ethereum.org/developers/docs/apis/json-rpc/#eth_syncing)[Solana RPC: getHealth](https://solana.com/docs/rpc/http/gethealth) ## Nonce (account nonce) EVM An EVM account nonce orders transactions authorized by an externally owned account. Transactions from the same sender must be processed in nonce order. A replacement competes for the same nonce, and a missing earlier nonce can hold later transactions pending. Read the appropriate pending or confirmed view when managing concurrent submissions. [Mempool (transaction pool)](https://supanode.xyz/glossary#mempool)[Raw (signed) transaction](https://supanode.xyz/glossary#raw-transaction)[Chain ID](https://supanode.xyz/glossary#chain-id)[Ethereum: account nonce](https://ethereum.org/developers/docs/accounts/)[Geth: transaction pool](https://geth.ethereum.org/docs/interacting-with-geth/rpc/ns-txpool) ## Pagination cursor General API A pagination cursor identifies where to continue reading an ordered result set. It may be an opaque token, a signature or another API-defined boundary. Preserve the documented direction and filters between requests. Deduplicate records and define an overlap strategy when the underlying history can change while a backfill is running. [History retention window](https://supanode.xyz/glossary#retention-window)[Chain reorganization (reorg)](https://supanode.xyz/glossary#reorg)[Horizon API: page arguments](https://developers.stellar.org/docs/data/apis/horizon/api-reference/structure/pagination/page-arguments)[Solana RPC: getSignaturesForAddress](https://solana.com/docs/rpc/http/getsignaturesforaddress) ## Preflight simulation (Solana) Solana Preflight validates and simulates a submitted Solana transaction before the RPC forwards it. It can detect problems such as an invalid signature, stale blockhash or failing instruction against the simulated state. Simulation success does not reserve state or guarantee later execution. Skipping preflight removes a check; it does not make an invalid transaction valid. [Recent blockhash (Solana)](https://supanode.xyz/glossary#blockhash)[Compute unit (Solana)](https://supanode.xyz/glossary#compute-unit)[Solana RPC](https://supanode.xyz/glossary#solana-rpc)[Solana: sendTransaction preflight checks](https://solana.com/docs/rpc/http/sendtransaction) ## Priority fee Solana / EVM A priority fee adds an inclusion incentive on top of the network's other transaction fee components. Solana expresses it through a compute-unit price and requested compute budget. EIP-1559 uses a priority price per gas subject to the total fee cap. A Jito bundle tip is a separate payment mechanism; none guarantees inclusion. [Compute unit (Solana)](https://supanode.xyz/glossary#compute-unit)[Base fee (EIP-1559)](https://supanode.xyz/glossary#base-fee)[Jito Bundles](https://supanode.xyz/glossary#jito-bundles)[Solana docs: fees](https://solana.com/docs/core/fees)[Ethereum.org: gas and fees](https://ethereum.org/developers/docs/gas/) ## Program derived address (PDA) Solana A program derived address is a deterministic address computed from seeds and a program ID that has no ordinary private key. The runtime lets the deriving program authorize operations for that PDA through signed cross-program calls. Deriving an address does not create an account there; the application still needs the relevant initialization instruction. [Associated token account (ATA)](https://supanode.xyz/glossary#associated-token-account)[Solana RPC](https://supanode.xyz/glossary#solana-rpc)[Solana docs: program derived addresses](https://solana.com/docs/core/pda) ## Rate limit (HTTP 429) General API A rate limit restricts a client's allowed request or resource consumption over a defined interval. HTTP 429 commonly signals that the allowance was exceeded. Check the service's scope, such as key, method or connection, and honor Retry-After when provided. Spreading retries with backoff avoids amplifying a temporary limit into continuous failure. [JSON-RPC](https://supanode.xyz/glossary#json-rpc)[WebSocket subscription](https://supanode.xyz/glossary#pubsub-subscription)[RFC 6585: 429 Too Many Requests](https://www.rfc-editor.org/rfc/rfc6585.html#section-4) ## Raw (signed) transaction EVM A raw transaction is the signed, serialized transaction payload ready for submission. An RPC node can relay those bytes without receiving the sender's private key. A successful send response normally identifies the transaction; inclusion and execution status require later checks. Signing for the correct chain and nonce remains the client's responsibility. [Chain ID](https://supanode.xyz/glossary#chain-id)[Nonce (account nonce)](https://supanode.xyz/glossary#nonce)[Transaction receipt](https://supanode.xyz/glossary#transaction-receipt)[EIP-155: signed transaction and replay protection](https://eips.ethereum.org/EIPS/eip-155)[Ethereum transaction format](https://ethereum.org/developers/docs/transactions/) ## Realized vs Unrealized PnL Trading concept Realized PnL measures gain or loss attributed to closed exposure; unrealized PnL values exposure that remains open at a chosen price. Results depend on cost-basis method, fees, funding, transfers and the valuation source. For a simple spot example before fees, selling 2 units bought at 10 for 12 realizes 4; 3 remaining units marked at 12 show 6 unrealized. [Copy Trading](https://supanode.xyz/glossary#copy-trading)[Slippage](https://supanode.xyz/glossary#slippage)[Hyperliquid: profit and loss calculations](https://hyperliquid.gitbook.io/hyperliquid-docs/trading/entry-price-and-pnl) ## Recent blockhash (Solana) Solana A recent blockhash binds a standard Solana transaction to a limited validity period. getLatestBlockhash returns a blockhash and lastValidBlockHeight. Track that height when deciding whether the transaction has expired. Durable nonce transactions use a different validity mechanism; repeatedly rebroadcasting expired bytes cannot refresh a recent blockhash. [Block height](https://supanode.xyz/glossary#block-height)[Preflight simulation (Solana)](https://supanode.xyz/glossary#preflight)[Solana RPC: latest blockhash](https://solana.com/docs/rpc/http/getlatestblockhash)[Solana transaction confirmation and expiration](https://solana.com/developers/guides/advanced/confirmation) ## Rent exemption (Solana) Solana Rent exemption is the minimum lamport balance required for an account's allocated data size under Solana's account model. Query the RPC calculation for the actual size rather than hard-coding a familiar wallet balance. This balance funds account storage requirements and is distinct from the transaction fee paid to create or modify the account. [Lamport](https://supanode.xyz/glossary#lamport)[Associated token account (ATA)](https://supanode.xyz/glossary#associated-token-account)[Solana docs: accounts](https://solana.com/docs/core/accounts)[Solana docs: terminology (rent)](https://solana.com/docs/references/terminology) ## Replay General streaming concept Replay redelivers previously produced records from an earlier position so a client can resume or backfill a stream. A replay request needs a supported starting position and enough server-side history. The replay window can be shorter than stored history. Consumers still need checkpoints, deduplication and fork handling; reconnecting a live subscription alone does not guarantee recovery. [History retention window](https://supanode.xyz/glossary#retention-window)[WebSocket subscription](https://supanode.xyz/glossary#pubsub-subscription)[Yellowstone gRPC](https://supanode.xyz/glossary#yellowstone-grpc)[Yellowstone subscription protocol: from\_slot](https://github.com/rpcpool/yellowstone-grpc/blob/master/yellowstone-grpc-proto/proto/geyser.proto) ## Sandwich Attack Trading concept A sandwich attack places transactions before and after a target trade to profit from the price movement that the target creates. A typical AMM example buys before the target buy and sells afterward. Slippage limits constrain acceptable execution but do not guarantee protection. The attack's feasibility depends on transaction visibility, ordering control and the trading venue. [MEV on Solana](https://supanode.xyz/glossary#mev-solana)[Slippage](https://supanode.xyz/glossary#slippage)[Jito Bundles](https://supanode.xyz/glossary#jito-bundles)[Ethereum: MEV and sandwich trading](https://ethereum.org/developers/docs/mev/) ## Sequence number (Stellar) Stellar reference A Stellar transaction sequence number controls ordering and replay protection for its source account. It is separate from the network's ledger sequence. Applications that submit concurrently from one account must coordinate sequence allocation. Specialized transaction preconditions and sequence operations exist, so inspect the transaction type before applying a simple increment rule. [Ledger (Stellar)](https://supanode.xyz/glossary#ledger-stellar)[Muxed account (Stellar)](https://supanode.xyz/glossary#muxed-account)[Stellar docs: glossary](https://developers.stellar.org/docs/learn/glossary)[Stellar docs: operations and transactions](https://developers.stellar.org/docs/learn/fundamentals/transactions/operations-and-transactions) ## Sequencer (L2) Rollups A sequencer orders a rollup's incoming transactions and produces the execution sequence users first observe. Sequencer acceptance gives an early view of the rollup, while parent-chain publication and settlement provide later assurances. A sequencer feed can be useful for timely observation, but its acknowledgement should not be described as every form of finality. [Layer 2 rollup](https://supanode.xyz/glossary#l2-rollup)[Finality](https://supanode.xyz/glossary#finality)[Arbitrum Orbit chain (Arbitrum chain)](https://supanode.xyz/glossary#arbitrum-orbit)[Arbitrum: sequencer](https://docs.arbitrum.io/how-arbitrum-works/deep-dives/sequencer) ## Server-Sent Events (SSE) General protocol / Stellar Server-Sent Events lets an HTTP server deliver a sequence of text events through one ongoing response. It is a server-to-client channel rather than a bidirectional socket. Clients can reconnect and send a last-event identifier, but actual resumption depends on the server's API and retained events. Horizon uses this pattern for supported resources. [Horizon (Stellar)](https://supanode.xyz/glossary#horizon)[WebSocket subscription](https://supanode.xyz/glossary#pubsub-subscription)[Replay](https://supanode.xyz/glossary#replay)[WHATWG HTML: server-sent events](https://html.spec.whatwg.org/multipage/server-sent-events.html)[Horizon API: streaming](https://developers.stellar.org/docs/data/apis/horizon/api-reference/structure/streaming) ## Shred (Solana) Solana A shred is a transport fragment of Solana ledger data used in block propagation. Consumers reconstruct and process these fragments to observe ledger contents. Receiving a fragment is earlier in the pipeline than confirming a complete transaction's final status; decoding, missing pieces and fork handling remain separate concerns. [Leader and leader schedule (Solana)](https://supanode.xyz/glossary#leader)[Slot](https://supanode.xyz/glossary#slot)[Commitment level](https://supanode.xyz/glossary#commitment-level)[Solana docs: terminology](https://solana.com/docs/references/terminology) ## Slippage Trading concept Slippage is the difference between the price or output expected for a trade and the result actually executed. A slippage tolerance sets an acceptable bound; it is not an extra fee. Market movement and available liquidity can change a quote, while price impact is the change caused by the trade itself. Keep the two concepts separate in execution reports. [Jupiter Aggregator](https://supanode.xyz/glossary#jupiter-aggregator)[Sandwich Attack](https://supanode.xyz/glossary#sandwich-attack)[Jupiter: slippage and quote parameters](https://developers.jup.ag/docs/swap/v1/get-quote) ## Slot Solana A slot is an indexed opportunity for an assigned leader to produce a block. Some slots are skipped or belong to a branch that does not become canonical. Slot numbers therefore advance independently of produced-block height. Use a returned slot as chain context rather than assuming it represents a precise wall-clock timestamp. [Block height](https://supanode.xyz/glossary#block-height)[Leader and leader schedule (Solana)](https://supanode.xyz/glossary#leader)[Epoch (Solana)](https://supanode.xyz/glossary#epoch)[Solana RPC: getSlot](https://solana.com/docs/rpc/http/getslot)[Solana: terminology](https://solana.com/docs/references/terminology) ## Solana RPC Solana Solana RPC is the network's API for reading chain state, inspecting transactions and submitting signed transactions, commonly using JSON-RPC over HTTP. It also defines WebSocket subscription methods. The API's methods and commitment settings are Solana-specific; JSON-RPC only supplies the message format. A provider's method availability, retention and limits must be checked separately. [JSON-RPC](https://supanode.xyz/glossary#json-rpc)[Commitment level](https://supanode.xyz/glossary#commitment-level)[WebSocket subscription](https://supanode.xyz/glossary#pubsub-subscription)[Solana RPC API](https://solana.com/docs/rpc) ## Solidified block (TRON) TRON reference A solidified block is a TRON block that has reached the protocol's irreversible confirmation stage. TRON's confirmation rules depend on its super representatives. Its full-node and solidity-node interfaces can expose different stages of history, so choose the API that matches the confirmation requirement instead of treating the newest block as irreversible. [Super representative (TRON)](https://supanode.xyz/glossary#super-representative)[Finality](https://supanode.xyz/glossary#finality)[TRON Developer Hub: consensus](https://developers.tron.network/docs/concensus)[TRON Developer Hub: confirmation semantics](https://developers.tron.network/docs/confirmation-semantics) ## Soroban and Stellar RPC Stellar reference Soroban is Stellar's smart-contract execution platform; Stellar RPC provides APIs for its simulation, submission and data access workflows. This interface complements Horizon's indexed resources. Contract events and historical data still depend on the RPC server's documented retention. Choosing Stellar RPC does not imply that every past event remains available indefinitely. [Horizon (Stellar)](https://supanode.xyz/glossary#horizon)[History retention window](https://supanode.xyz/glossary#retention-window)[Ledger (Stellar)](https://supanode.xyz/glossary#ledger-stellar)[Stellar docs: glossary](https://developers.stellar.org/docs/learn/glossary)[Stellar docs: Horizon (Soroban data served by Stellar RPC)](https://developers.stellar.org/docs/data/apis/horizon) ## State root EVM A state root is the hash that commits a block to its resulting global account state. It enables proofs of selected account or storage values against that block. The root is different from the block hash, transaction root and receipt root. Verification needs both a correct proof and a trusted block context. [Merkle proof (eth\_getProof)](https://supanode.xyz/glossary#merkle-proof)[Archive node](https://supanode.xyz/glossary#archive-node)[Ethereum: block data](https://ethereum.org/developers/docs/blocks/)[EIP-1186: state proofs](https://eips.ethereum.org/EIPS/eip-1186) ## Stock Token (Robinhood Chain) Robinhood Chain A Robinhood Stock Token is an ERC-20 representation of a tokenised debt security providing economic exposure to an underlying share or ETF under the issuer's terms. It does not itself grant ownership rights in the underlying security. Integration code must follow the issuer's balance-display and corporate-action rules; an ERC-20 transfer alone does not describe the complete economic or legal position. [ABI (application binary interface)](https://supanode.xyz/glossary#abi)[Event log](https://supanode.xyz/glossary#event-log)[Arbitrum Orbit chain (Arbitrum chain)](https://supanode.xyz/glossary#arbitrum-orbit)[Robinhood Chain docs: Stock Tokens](https://docs.robinhood.com/chain/stock-tokens/)[Robinhood Chain docs: Building with Stock Tokens](https://docs.robinhood.com/chain/building-with-stock-tokens/) ## Stroop (Stellar) Stellar reference A stroop is one ten-millionth of a lumen, Stellar's native XLM unit. Integer stroop amounts are useful for representing fees without decimal rounding. Stellar classic asset amounts also use seven decimal places, but an asset's symbol alone does not establish its issuer or economic value. [Ledger (Stellar)](https://supanode.xyz/glossary#ledger-stellar)[Stellar docs: glossary](https://developers.stellar.org/docs/learn/glossary) ## Super representative (TRON) TRON reference A super representative is an elected TRON block producer in its delegated proof-of-stake system. Votes determine the active producer set under network rules. Super representatives participate in producing and confirming blocks; the role differs from an API provider that merely serves chain data to applications. [Solidified block (TRON)](https://supanode.xyz/glossary#solidified-block)[Energy and bandwidth (TRON)](https://supanode.xyz/glossary#energy-and-bandwidth)[TRON Developer Hub: consensus](https://developers.tron.network/docs/concensus) ## Transaction receipt EVM A transaction receipt records the result of a transaction that was included in a block. It includes execution status, gas accounting and emitted logs. A successful RPC submission can precede the existence of a receipt, and receipt availability does not itself imply finality. Check both status and the required confirmation stage. [Event log](https://supanode.xyz/glossary#event-log)[Gas](https://supanode.xyz/glossary#gas)[Finality](https://supanode.xyz/glossary#finality)[Ethereum JSON-RPC API: eth\_getTransactionReceipt](https://ethereum.org/developers/docs/apis/json-rpc/#eth_gettransactionreceipt) ## Transaction trace EVM A transaction trace exposes internal execution activity, such as nested calls or opcode steps, by instrumenting or replaying execution. Its shape depends on the client's tracer. Traces can reveal calls absent from event logs, but are not a standardized list of independent transactions. Availability and historical depth depend on the node and tracing API. [Event log](https://supanode.xyz/glossary#event-log)[Archive node](https://supanode.xyz/glossary#archive-node)[Transaction receipt](https://supanode.xyz/glossary#transaction-receipt)[Geth: built-in tracers](https://geth.ethereum.org/docs/developers/evm-tracing/built-in-tracers) ## TRC-20 TRON reference TRC-20 defines a fungible-token contract interface for TRON, including balance, transfer and allowance operations. The interface resembles ERC-20, but transaction submission, address encoding and resource charging follow TRON. Reusing an EVM transaction payload or address string without conversion is not enough to call a TRC-20 contract correctly. [TRON address formats (hex 41 and Base58)](https://supanode.xyz/glossary#hex-41-address)[Energy and bandwidth (TRON)](https://supanode.xyz/glossary#energy-and-bandwidth)[TRON Developer Hub: TRC-20 contract interaction](https://developers.tron.network/docs/trc20-contract-interaction) ## TRON address formats (hex 41 and Base58) TRON reference TRON represents an account address as a network-prefixed hexadecimal value or a Base58Check string commonly beginning with T. These representations can name the same account. Some HTTP APIs select the expected form using a visible parameter. Decode and encode with the documented format rather than adding or removing characters by eye. [TRC-20](https://supanode.xyz/glossary#trc-20)[TRON Developer Hub: accounts](https://developers.tron.network/docs/account) ## WebSocket subscription Solana / EVM A WebSocket subscription asks a server to push selected updates over an open bidirectional connection. Subscriptions are tied to the connection and API semantics. After a disconnect, reconnect, resubscribe and recover missed data using an available history or replay mechanism. A live stream alone is not a durable event queue. [Replay](https://supanode.xyz/glossary#replay)[JSON-RPC](https://supanode.xyz/glossary#json-rpc)[Commitment level](https://supanode.xyz/glossary#commitment-level)[Geth: real-time events (pub/sub)](https://geth.ethereum.org/docs/interacting-with-geth/rpc/pubsub)[Solana RPC: WebSocket methods](https://solana.com/docs/rpc/websocket) ## Wei and gwei Ethereum / EVM reference Wei is Ethereum's smallest native denomination; one ETH is 10^18 wei, and one gwei is 10^9 wei. Gas prices are often displayed in gwei, while RPC quantities use integer values. An EVM-compatible chain can use a different native currency, so name the network's currency rather than labeling every fee ETH. [Gas](https://supanode.xyz/glossary#gas)[Base fee (EIP-1559)](https://supanode.xyz/glossary#base-fee)[Ethereum.org: intro to ether (denominations)](https://ethereum.org/developers/docs/intro-to-ether/) ## Workchain (TON) TON reference A workchain is a distinct TON chain domain with its own account space and execution rules within the wider network. An internal address includes the workchain ID as well as the account identifier. Workchains may be divided into shards. Omitting the workchain context can make otherwise similar account identifiers refer to different destinations. [Masterchain (TON)](https://supanode.xyz/glossary#masterchain)[Bounceable address (TON)](https://supanode.xyz/glossary#bounceable-address)[TON: chain domains and address space](https://docs.ton.org/foundations/addresses/overview) ## Yellowstone gRPC Solana Yellowstone gRPC is an open-source streaming service and protocol built around Solana Geyser data. Clients subscribe to selected accounts, transactions, slots and other supported updates using protobuf messages over gRPC. Filtering, commitment and replay support depend on the server implementation and configuration. A gRPC connection does not imply that its data is already decoded into application-specific trades. [Geyser Plugin](https://supanode.xyz/glossary#geyser-plugin)[Replay](https://supanode.xyz/glossary#replay)[Commitment level](https://supanode.xyz/glossary#commitment-level)[Yellowstone gRPC upstream documentation](https://github.com/rpcpool/yellowstone-grpc) --- Source: https://supanode.xyz/glossary