Riverstone Networks 7450 - Manual (Page 8)

The Alcatel-Lucent 7450 ESS is the industry’s first
Ethernet service switch with carrier high availability.
More than ever, high availability is at the forefront of
the service provider’s criteria for consumer and business
Ethernet services. The demand for high availability has
been most pronounced at the service provider edge where
thousands of connections are hosted and availability
options may be limited for WAN Ethernet services and
service-aware Ethernet aggregation for consumer triple
-play services.
The Alcatel-Lucent 7450 ESS architecture has been
developed to meet the stringent requirements for sup-
porting mission-critical applications and services, and a
number of high availability features have been designed
into the 7450 ESS:
• Non-Stop Routing — The Alcatel-Lucent 7450 ESS
provides true stateful resiliency of the interior
gateway protocol (IGP) routing processes such that
all topology information and adjacencies are main-
tained even in the event of a failure of one SF/CPM.
The 7450 ESS supports non-stop routing for open
shortest path first (OSPF) and intermediate system-
to-intermediate system (IS-IS).
• Non-Stop Services — The Alcatel-Lucent 7450 ESS
also provides stateful resiliency for protocols that run
over the IGP such as MPLS. The 7450 ESS supports
non-stop services for VPLS and VLL using tunnels
created by label distribution protocol (LDP), targeted
LDP, generic routing encapsulation (GRE) and static
label switched path (LSP) tunnels.
• Graceful Restart Helper — This feature improves
availability in cases where the Alcatel-Lucent 7450
ESS is peering with routers not otherwise capable of
non-stop routing or services.
Highly Reliable Carrier Ethernet Services
Figure 5. The Evolution of Ethernet Services to Carrier Reliability
5. Non-stop Services (NSS)
• Zero service downtime with NSS (VPLS, VLL)
7450 ESS is the industry’s first
Ethernet service switch with
carrier high availability
Milliseconds
00:00:00:0 X
Minutes
00:0 X : XX : XX
4. MPLS Fast Re-Route
• Delivers sub 50 ms failover with thousands of services enabled
3. 802.1w Rapid Spanning Tree Protocol (RSTP)
802.1s Multiple VLAN Spanning Tree (MVST)
• Re-convergence time can range from subsecond to subminute
2. 802.3ad Link Aggregation
• Ethernet connections combined to load share and provide better resiliency
1. 802.1D Spanning Tree
• Spanning tree protocol (STP) solves loops by removing all redundant paths
7450 ESS
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Business Services and Triple Play
Internet Access
Beginning
“As service convergence over IP networks accelerates, high availability and reliability become important
not only for business services, but also for demanding residential applications such as IPTV and online
gaming. High availability is moving from being a requirement for business services, to a requirement
for all services.”
MARK SEERY, RHK.
8 Alcatel-Lucent 7450 Ethernet Service Switch