General DataComm SpectraComm IP T1, Руководство по установке и эксплуатации

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Application Guidelines Using Sub-interfaces for Frame Relay PVCs
076R200-000 SpectraComm IP T1 Router Card A-7
Issue 13 Installation and Operation Manual
Using Sub-interfaces for Frame Relay PVCs
To support Frame Relay PVCs, you must add sub-interfaces on the
serial0
or
serial1
interface using the
configure interfaces add-sub
command. Sub-interface names take
the form
serial
n
.
nnn where n =
0
or
1
and nnn =
1
-
999
. Each sub-interface must have a
DLCI mapped to it before IP data can be forwarded on the sub-interface. Use the
configure
frame-relay interface-dlci
command to assign a DLCI to a sub-interface and then
configure its IP encapsulation. Once added, sub-interfaces can be assigned an IP address, etc.
IP Addresses
The SCIP is a routing network device that provides IP connectivity to other devices at a remote site.
Each network interface on the SCIP requires a unique numeric IP address which provides the
network prefix and the host number. Addresses are expressed in dotted decimal notation which
defines the 32-bit IP address in four 8-bit fields (or ‘four octets’), e.g.,
195.88.11.4
.
Each octet has a value from 000 to 255.
Using the traditional Class A, B, and C network architectures, one or more octets would be allocated
to the network prefix and host number. The more octets allocated to a network prefix, the larger the
number of networks anticipated; likewise, the more octets allocated to a host number, the larger the
number of hosts anticipated.
Table A-2 describes the traditional uses of these general purpose
network architectures.
IP Addressing Examples
An example is shown below of both classical and shortened IP address representations:
Example: Classical IP notation:
IP-address ::= <
Network-prefix
> <
Host-number
>
192.168.11.1
with a subnet mask of
255.255.255.0
Example: Shortened IP notation:
192.168.11.1/24
where the
/24
indicates that the first 3 octets comprise the network prefix.
Table A-2 Class-Based IP Routing
Network Class 1st Octet 2nd Octet 3rd Octet 4th Octet
Class A NETWORK Prefix
Up to 126 networks
HOST Number
~17,000,000 hosts each
Class B NETWORK Prefix
~65,000 Networks
HOST Number
~17,000 hosts each
Class C NETWORK Prefix
~ 2,000,000 Networks
HOST Number
254 hosts each