Zte ZXR10 GER, Руководство пользователя

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ZXR10 GER (V2.6.03) General Excellent Router User Manual Volume-I
290 Confidential and Proprietary Information of ZTE CORPORATION
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Administrator (ADM) domain: Identifies an administration
assignment number
If the value of the type domain is 0, administrator domain
contains an IPv4 address. RFC2547bis recommends that IP
address of a router (this address is normally configured as
router ID) be used, and this address is a public address.
If the type domain is 1, the administrator domain contains
an AS ID. RFC2547bis recommends a public AS ID allocated
by IANA be used (it is much better that the AS ID of the ISP
or customer itself is used).
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Assignment Number (AN) domain: a number assigned by a
network carrier
If the type domain is 0, length of the AN domain is two bytes.
If the type domain is 1, length of the AN domain is four bytes.
An RD is only used between PEs to differentiate IPv4
addresses of different VPNs. The ingress generates an RD
and converts the received IPv4 route of the CE into a VPN-
IPv4 address. Before advertising the route to the CE, the
egress PE converts the VPN-IPv4 route into an IPv4 route.
Operational Principles of MPLS VPN
Basic operation mode of MPLS VPN is the application of the L3
technologies. Each VPN has an independent VPN-ID, users of
each VPN can only communicate with members in the same VPN
and only VPN members can enter the VPN.
On MPLS-based VPNs, the service provider assigns a
distinguisher to each VPN, called Route Distinguisher (RD). The
distinguisher is unique in the network of the service provider.
Forwarding table contains a unique address, called VPN-IP
address, which is formed through the connection of the RD and
the IP address of the user. The VPN-IP address is a unique one
in the network. The address table is stored in the forwarding
table.
BGP is a routing information distribution protocol, which uses
multi-protocol extension and common attributes to define VPN
connectivity. On MPLS-based VPNs, BGP only advertises
information to members in the same VPN and provides basic
security by means of traffic split.
Data is forwarded by using LSP. The LSP defines a special path
that cannot be changed, to guarantee the security. Such a label-
based mode can provide confidentiality as frame relay and ATM.
The service provider relates a special VPN to an interface, and
packet forwarding depends upon ingress labels.
MPLS
Operational
Principles
Forwarding
table