Terminology

2185 terms, tools, patterns and metrics an architect is expected to use precisely. Each one gets a short explanation of what it is, and — where it matters — what it is commonly confused with. Search filters as you type; the column headers sort.

All areas2185 Architecture Fundamentals77 Distributed Systems107 Data Architecture110 Cloud Architecture89 Networking88 API & Integration Architecture82 Reliability & Resilience75 Observability70 Performance & Capacity Engineering72 Security Architecture81 Cost Architecture & FinOps66 Business Architecture67 Architecture Communication67 Enterprise Architecture66 Legacy Modernization66 AI-Era Architecture69 Software Architecture & Engineering71 Architecture Patterns71 Architecture Decision-Making63 The Architect's Meta-Skills61 Delivery & Release Engineering66 Platform Engineering & Developer Experience70 Testing & Quality Architecture66 Data Platform Architecture64 Streaming & Real-Time Data69 Data Governance & Semantics69 Frontend & Experience Architecture66 Edge, Mobile & IoT68 Regulatory & Data Protection Architecture65 Assurance, Audit & Model Risk64

Kind Any concept785 practice729 pattern362 metric125 case-study77 tool62 protocol45

88 terms shown.

Term	Kind	Topic	What it is
Reverse Proxy in Practice	pattern	Reverse Proxies	A server that sits in front of origins and terminates, caches, routes and protects — the cheapest place to solve several problems at once.
Round-Trip Time RTT, Latency Floor	metric	Network Performance	The time for a packet to travel to a destination and back — a physical floor that no application optimisation can reduce.
Route Origin Validation ROV, RPKI Origin Validation	practice	Routing & BGP	Checking a BGP announcement's origin against a signed authorisation before accepting it, so a more specific prefix announced by the wrong network is dropped instead of winning.
Route Propagation	concept	Routing & BGP	Automatically inserting routes learned from a VPN or dedicated connection into a route table, rather than maintaining them by hand.
Route Table	concept	Subnetting	The set of rules deciding where traffic leaving a subnet is sent, and the thing that actually makes a subnet public or private.
Security Group Firewall Rules, NSG	tool	Networking	A stateful, instance-level firewall that allows specified traffic and denies everything else by default.
Server Name Indication SNI, TLS Host Extension	protocol	TLS & Certificates	The cleartext hostname a client sends in its first TLS message, letting one address serve many certificates and letting a proxy route a session before it decrypts anything.
Server-Sent Events SSE, EventSource	protocol	WebSockets & Realtime	A one-way streaming protocol over plain HTTP in which the server pushes text events to the client on a long-lived response.
Service Mesh Networking	concept	Service Mesh Networking	What a mesh actually does at the network level, the cost per hop, and the shift from sidecar to shared-proxy models.
Source NAT SNAT, Masquerading	concept	NAT & Egress	Rewriting the source address of outbound packets so that many private addresses share one public address, with a translation table mapping replies back.
Stateful Packet Filtering	concept	Firewalls & Security Groups	Filtering that tracks connection state, so return traffic for an allowed outbound connection is permitted automatically.
Subnet	concept	Networking	A subdivision of a network's address range, used as the unit of routing and, in cloud, of availability-zone placement.
Subnet Sizing	practice	Subnetting	Choosing subnet prefix lengths with enough headroom, given that subnets cannot be resized and cloud providers reserve several addresses in each.
Subnetting and Address Planning	practice	Subnetting	Dividing address space across zones and tiers, and the exhaustion failures that appear only at container density.
TCP Handshake	protocol	TCP/IP	The three-way SYN / SYN-ACK / ACK exchange that establishes a TCP connection, costing one round trip before any data moves.
TCP/IP	protocol	Networking	The layered protocol suite underneath essentially all application traffic — IP routes packets, TCP turns them into a reliable ordered stream.
TCP/IP for Architects	protocol	TCP/IP	What an architect actually needs from the transport layer — handshake cost, congestion behaviour, head-of-line blocking, and when to abandon TCP entirely.
TLS Transport Layer Security, SSL	protocol	Networking	The protocol that gives a network connection encryption, integrity and server authentication, underneath HTTPS and most other secure transports.
Traffic Splitting	pattern	Service Mesh Networking	Directing a defined percentage or subset of requests to a different version of a service, configured at the routing layer rather than in application code.
Trust Boundary Classification Where mTLS Is Required, Encryption Scope	practice	TLS & Certificates	Writing down which network segments count as trust boundaries, so that mutual TLS is applied where it changes the security posture rather than uniformly or by intuition.
Virtual Private Cloud VPC, VNet	concept	Networking	A logically isolated network inside a cloud provider, with an address range you control and explicit rules for what may enter and leave.
VPC Design	practice	VPC Design	How virtual networks, subnets and connectivity are structured — decisions that are cheap now and extremely expensive to change later.
VPC Peering	concept	VPC Design	A direct network connection between two VPCs, which is simple, cheap and non-transitive — the last property being the one that shapes topology.
VPN vs Dedicated Connection Direct Connect, ExpressRoute	concept	Private Connectivity	Two ways to link on-premises networks to cloud — an encrypted tunnel over the internet, or a private physical circuit.
WebSocket	protocol	Networking	A protocol that upgrades an HTTP connection into a persistent, full-duplex channel so the server can push to the client without polling.
WebSocket Backplane	pattern	WebSockets & Realtime	A shared publish/subscribe layer letting a message published on one server reach clients connected to a different server.
WebSockets	protocol	WebSockets & Realtime	A persistent bidirectional connection over HTTP — the right tool for server-initiated updates, and a stateful component in an otherwise stateless architecture.
X-Forwarded-For Forwarded Header	concept	Reverse Proxies	The header chain recording original client addresses through a series of proxies — and a value that must never be trusted without knowing the topology.