Alcatel-Lucent 7750 SR OS - Introduction; Service Types

Introduction
Page 26 7750 SR OS Services Guide
Introduction
A service is a globally unique entity that refers to a type of connectivity service for either Internet
or VPN connectivity. Each service is uniquely identified by a service ID within a service area. The
SR-Series service model uses logical service entities to construct a service. In the service model,
logical service entities provide a uniform, service-centric configuration, management, and billing
model for service provisioning.
Services can provide Layer 2/bridged service or Layer3/IP routed connectivity between a service
access point (SAP) on one SR-Series router and another service access point (a SAP is where
traffic enters and exits the service) on the same (local) or another SR-Series router (distributed). A
distributed service spans more than one router.
Distributed services use service distribution points (SDPs) to direct traffic to another SR-Series
through a service tunnel. SDPs are created on each participating SR-Series, specifying the
origination address (the SR-Series router participating in the service communication) and the
destination address of another SR-Series. SDPs are then bound to a specific customer service.
Without the binding process, far-end SR-Series devices are not able to participate in the service
(there is no service without associating an SDP with a service).
Service Types
The SR-Series offers the following types of subscriber services which are described in more detail
in the referenced chapters:
• Virtual Leased Line (VLL) services:
→ Ethernet pipe (Epipe) — A Layer 2 point-to-point VLL service for Ethernet frames.
See Ethernet Pipe (Epipe) Services on page 110.
→ ATM VLL (Apipe) — A point-to-point ATM service between users connected to 7750
nodes on an IP/MPLS network. See ATM VLL (Apipe) Service Overview on page
170.
→ Frame-Relay (Fpipe) — A point-to-point Frame Relay service between users
connected to 7750 nodes on the IP/MPLS network. See Frame Relay VLL (Fpipe)
Service Overview on page 172.
→ IP Pipe (Ipipe) — Provides IP connectivity between a host attached to a point-to-point
access circuit (FR, ATM, PPP) with routed IPv4 encapsulation and a host attached to
an Ethernet interface. See IP Interworking VLL (Ipipe) Overview on page 178.
• Virtual Private LAN Service (VPLS) — A Layer 2 multipoint-to-multipoint VPN. See
Virtual Private LAN Service on page 323. VPLS includes Hierarchical VPLS (H-VPLS)
which is an enhancement of VPLS which extends Martini-style signaled or static virtual
circuit labeling outside the fully meshed VPLS core.