Zte ZXR10 8900E series, Описание продукта

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ZXR10 8900E series Core Switch Product Description
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
Support LDP and RSVP protocols;

Support TTL value decreasing, loop test, policy management and pop up at the last
but one hop;

Support downstream independent label distribution mode and free label reservation
mode;
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Support fast rerouting of LSP and establishment of RSVP-LSP.
3.3.2 MPLS TE
Network congestion is a major problem that affects backbone network performance. The
reason of congestion may be insufficient network resource or unbalanced network
resource load which leads to local congestion. Traditional routing with shortest path first
will cause unbalanced distribution of network traffic, that is, when a path is congested, the
traffic will not be switched to other paths. With the expansion of network scale and
development of network services, the customers have increasingly higher requirements
for service quality; the problem of traditional routing is thoroughly exposed. TE (Traffic
Engineering) is just to solve the congestion caused by unbalanced load. MPLS TE is a
technology integrating traffic engineering with MPLS. By MPLS TE, the service provider
can precisely control the path of the traffic, so as to avoid the congested node, solving the
problem of some paths being overloaded and some paths being idle and making full use
of the current bandwidth resource. At the same time, MPLS TE can reserve resource
when establishing LSP tunnel to guarantee service quality.
MPLS TE creates link bandwidth resource database in the nodes of the MPLS network
via OSPF TE or IS-IS TE, calculates tunnel creation path by CSPF algorithm according to
link bandwidth resource database and tunnel restriction conditions, and finally creates TE
tunnel using RSVP-TE signaling protocol in the path calculated by CSPF algorithm.
RSVP (Resource Reservation Protocol) is a TCP/IP based transport layer protocol. By
RSVP, the host can apply for specific QoS to the network, providing secure data stream
services for specific services, and meanwhile reserve resource on the router nodes
where the data stream passes and keep this status until the service releases
corresponding resource. RSVP-TE protocol, an extended protocol of RSVP, can carry
parameters including bandwidth, some specific routes and color, create the LSP that
meets the restriction conditions according to traffic engineering route calculation and
complete link backup, node backup and load balance functions.
ZXR10 8900E supports MPLS TE-related technology and can provide the following
features:

MPLS TE provides “non-IGP shortest path first” IP packet forwarding capability,
which can effectively avoid network congestion caused by unbalanced network
traffic by planning network resource reasonably.