Zte ZXR10 GER, Руководство пользователя

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ZXR10 GER (V2.6.03) General Excellent Router User Manual Volume-I
268 Confidential and Proprietary Information of ZTE CORPORATION
and also fragmentation is needed, an ICMP message will be
returned (the type is 3, the code is 4, with the MTU of the
interface included).
When a router receives an IP datagram, if the destination
address is a local address and the protocol field of the header is
47, it indicates that the datagram has experienced GRE, so
resolution on the local router is needed. After validity check, the
GRE packet should be mapped to the locally saved GRE tunnel
ID according to the source and destination addresses of the GRE
packet. If the corresponding GRE tunnel does not exist, the
datagram will be dropped and then the GRE options will be
processed subsequently. System supports the key
、
sequence
、
checksum options. If the key tag in the flag field in the GRE
header is different from the key tag of the corresponding tunnel,
or the key tags are configured but the key values are different,
the datagram will be dropped.
Minus 1 from the TTL of the resolved IP data header, further
process it. A routing process is used to judge whether the
datagram is to be locally sent or forwarded.
Configuring GRE
Below procedure gives information about GRE configuration.
Router Command Line Interface has been accessed.
1. To create a tunnel and enter into the interface configuration
mode of the tunnel, use interface <tunnel-number>
command in global configuration mode as shown in Table
314.
T
A B L E
3 1 4 I
N T E R F A C E
T
U N N E L
C
O M M A N D
Command
Format Command
Mode
Command Function
interface
<tunnel-
number>
Global
configuration
This creates a tunnel and
enables to enter into the
interface configuration mode of
the tunnel
Result: This creates a tunnel and enables to enter into the
interface configuration mode of the tunnel.
2. To configure a source address for the tunnel, use
tunnel
source <ip-address> command in tunnel configuration
mode as shown in Table 315.
Key Tag
IP Data
Header-TTL
Purpose
Prerequisite
Steps