GamingGaming GlossaryPart 2 of 8
Clients and Delivery Glossary
39 terms from the Gaming book's Clients and Delivery part, each defined in a line and linked to the chapter that explains it.
- Activities (PS5): cards in the PlayStation 5 Control Center that take a player straight into a level or challenge, which a front end can only honor if every mode is reachable by a deep link (Game Clients & Launchers).
- Ad mediation: a client SDK and service that sits between the game and many ad networks and picks the best-paying ad for each slot, such as AppLovin MAX or Unity LevelPlay (Mobile Games).
- AdAttributionKit, SKAdNetwork: Apple's aggregated, privacy-preserving install attribution, which sends delayed postbacks to the winning ad network instead of exposing a device identifier; AdAttributionKit is the successor (Mobile Games).
- Advertising ID, IDFA: the resettable device identifiers for advertising on Android and iOS; on iOS the IDFA is all zeros unless the player allows tracking through ATT, and an Android user can delete the Advertising ID (Mobile Games).
- ATT (App Tracking Transparency): Apple's permission prompt an app must show before tracking a user or reading the IDFA; a game may not reward players for accepting it (Mobile Games).
- Background patching: a launcher downloading and installing patches while it's open, so the game is ready when the player is; the EA app advertises background updates and the Riot Client added them as an opt-in in May 2023 (Game Clients & Launchers).
- Binary delta, delta patch: a new file encoded as copy and insert instructions against one known old version (bsdiff, Courgette, zstd
--patch-from); smallest for that version, but a release needs a patch per supported old version (Patching & Content Delivery). - Boot set: the plugins a client loads before it's usable; League's Affinity mechanism for choosing it broke in 2018, so every plugin loaded at bootstrap, which is why the boot set needs an owner and a CI gate (Game Clients & Launchers).
- Bundle: a CDN object grouping many chunks so a download needs few requests; League's data is over 300,000 chunks in fewer than 5,000 bundles, over 85% shared with the previous version (Patching & Content Delivery).
- CEF (Chromium Embedded Framework): a BSD-licensed project for embedding Chromium in other applications; launchers such as Steam's, Battle.net's and the League client's draw their UI with an embedded Chromium, and Guild Wars 2 uses it inside the game (Game Clients & Launchers).
- Channel, staged exposure: a live or test channel per platform and region that points at one signed release at a time, and moving a release to a share of players or a region at a time while watching failures and crashes (Patching & Content Delivery).
- Chunk (content), content-defined chunking: a variable-size piece of a file, cut where a rolling hash meets a condition and named by its hash, so an insertion shifts only nearby chunks and identical chunks deduplicate; FastCDC is the algorithm League's patcher builds on (Patching & Content Delivery).
- Conversion value: the value an iOS app sets for AdAttributionKit postbacks, a 6-bit fine value (0 to 63) in the first postback or a coarse low, medium or high; the schema that maps early player behavior onto it is versioned config (Mobile Games).
- CPI, eCPI: cost per install, the agreed price per install, and effective CPI, ad spend divided by attributed installs when campaigns are bought on another basis (Mobile Games).
- Device tier: a small set of named quality levels, each a bundle of settings, with a versioned rule served from the backend that assigns each device to one (Mobile Games).
- Front-end client: the out-of-game client a player uses between matches, for sign-in, patching, the store, social features, queues and launching the game process (Game Clients & Launchers).
- Game Client API, LCU: Riot's supported, read-only local HTTPS interface in the running game at
127.0.0.1:2999(including the Live Client Data API), against the League Client API between CEF and the client's C++ services, which Riot doesn't support for third parties; Counter-Strike's Game State Integration is the push-based counterpart (Game Clients & Launchers). - Go-live switch: flipping the new manifest, the new minimum version and the new server builds at one instant, after preloads have put most bytes on disk, for a game where everyone moves together (Patching & Content Delivery).
- Host process: the long-lived client process that owns local services and canonical state (session, social, patching, game launch), so the UI can be closed during a match and rebuilt (Game Clients & Launchers).
- Install Referrer: Google Play's API that gives an installed app the referrer URL and click and install timestamps, tying an install to its click without a device identifier (Mobile Games).
- Jetsam, LMK: the OS killing an app to reclaim memory, called jetsam on iOS and done by the low-memory killer on Android; to the player it looks like a crash, but crash reporters often miss it (Mobile Games).
- Launcher: a program that installs, patches and launches games, with news and a store page, such as Steam, the Epic Games Launcher, Battle.net, the EA app, Ubisoft Connect and the Riot Client (Game Clients & Launchers).
- Lookback window: how long after an ad click or impression an install can still be attributed to it; measurement partners default to 7 days for clicks (Mobile Games).
- Loopback API: a client's local service interface bound to
127.0.0.1on a port chosen at startup, requiring a per-session secret and rejecting browser origins it doesn't own (Game Clients & Launchers). - Manifest: the list of every file and chunk in a release by content hash, which launchers and patchers read; League's is about 8 MB, signed, and the client loads nothing unsigned (Patching & Content Delivery; the build's own manifest is in Production Pipelines & Builds).
- Minimum supported version: the oldest build allowed to sign in or queue for a game and platform, checked at startup and before queueing with an "update required" screen (Patching & Content Delivery).
- MMP (mobile measurement partner): a client SDK and service, such as AppsFlyer or Adjust, that matches installs to ad clicks and impressions, collects forwarded postbacks and reports per campaign; its revenue figures are not the ledger (Mobile Games).
- Network protocol version: a deliberate version carried on every connection and bumped when the wire format changes, not on every build, so servers and matchmaking can decide compatibility (Patching & Content Delivery).
- Payback day: the first day N on which a cohort's ROAS reaches 100% (Mobile Games).
- Plugin (client): an independently owned and versioned unit of a client, front end (UI in CEF) or back end (C++ services); a League client build is a JSON list of plugins whose semver dependencies must resolve (Game Clients & Launchers).
- Postback, crowd anonymity tier: the delayed attribution message a device sends to the ad network after an install, and the tier Apple assigns by how many installs share the campaign, which decides how much detail the postback carries (Mobile Games).
- RADS: League's binary-delta patcher for eight years; its 2019 chunked replacement downloaded 22% more on patch 9.9 but cut average update time from over 8 minutes to under 40 seconds and failures from 2.2% to 0.3% (Patching & Content Delivery).
- ROAS (day N): return on ad spend: net revenue from a campaign's attributed install cohort over days 0 to N divided by its ad spend; it always carries its day (Mobile Games).
- Rollback (release): pointing a channel at the previous manifest, recorded as a new release with a higher sequence number so clients that refuse older manifests still accept it; not rollback netcode (Patching & Content Delivery).
- S2S reward callback: the server-to-server call an ad network or mediation platform makes when a rewarded ad completes, signed and retried, which the game verifies and grants on once, keyed by the network's event ID (Mobile Games).
- SteamPipe, depot: Steam's content system, which splits files into roughly 1 MB chunks, patches with binary deltas and publishes each depot build with a 64-bit manifest ID to branches (Patching & Content Delivery).
- Streaming install, launch set: Xbox's way of letting a title start once the data it needs to run is installed, with the rest installing in the background (Patching & Content Delivery).
- Thermal state, thermal headroom: the OS's report of how hot the device is (iOS nominal to critical; Android's thermal status levels) and Android's forecast of how close it is to throttling, which drive a game's step-down ladder (Mobile Games).
- Updater attacks (rollback, freeze): serving an older release to reinstall a vulnerable version, or the same old metadata forever, among the attacks a patcher must resist; defended by signed manifests, monotonic release numbers and short expiry (Patching & Content Delivery; the full list is in Software Updates).