Technical Documentation

Example: Channelized T1 IQ Interface Configuration

Figure 1: Channelized T1 IQ Interface Example

Image g017133.gif

The following example shows two ways to configure a channelized T1 IQ interface. Figure 1 shows a fractional T1 method and the NxDS0 method seen previously in the complex OC12 configuration example (see Example: Complex Configuration for a Channelized OC12 IQ Interface). The NxDS0 method breaks the channelized T1 IQ interface into discrete DS0 blocks, whereas the fractional method creates a clear channel T1 that is segmented by time slots.

To configure NxDS0 channels, include the partition statement at the [edit interfaces ct1-fpc/pic/port] hierarchy level. Include the timeslots and interface-type ds options to create the desired number of NxDS0 interfaces in time slots 1 through 24.

To configure a clear channel T1 on a channelized T1 IQ interface, include the no-partition statement with the interface-type t1 option at the [edit interfaces ct1-fpc/pic/port] hierarchy level. After you commit this configuration, you can create a fractional T1 on the clear channel T1 interface. To do so, include the timeslots statement at the [edit interfaces t1-fpc/pic/port t1-options] hierarchy level and specify the number of DS0 blocks to be allowed in the fractional T1 interface. The minimum number of 64-Kbps DS0 blocks you can configure is 1 and the maximum is 24.

Usually, you configure loopback statements at the controller level for all IQ-based channelized interfaces. One exception for channelized T1 IQ interfaces is that you must configure a payload loopback on a T1 IQ interface instead of the controller-level channelized T1 IQ interface. To configure, include the payload option at the [edit interfaces t1-fpc/pic/port t1-options loopback] hierarchy level.

Router A—NxDS0 Method

[edit]interfaces {ct1-2/3/7 {partition 1 timeslots 10 interface-type ds; # Creates NxDS0 channel ds-2/3/7:1.partition 2 timeslots 1-9 interface-type ds; # Creates a channel group with}              # 9 NxDS0s.ds-2/3/7:1 {unit 0 {family inet {address 10.25.1.2/24;}}}ds-2/3/7:2 {unit 0 {family inet {address 10.25.2.2/24;}}}}

Router A—Fractional T1 Method

[edit]interfaces {ct1-2/3/8 {no-partition interface-type t1; # This creates a single T1 channel: t1-2/3/8.}t1-2/3/8 {t1-options {timeslots 1-2; # This statement enables only 2 of the 24 NxDS0 time slots}             # available on t1-2/3/8.unit 0 {family inet {address 10.255.126.2/24;}}}}

Verifying Your Work

To verify correct operation of a channelized T1 IQ interface, use the following commands:

  • show interfaces
  • show interfaces controller

To view the interface names of the physical channelized T1 IQ interface and the resulting interfaces configured on the channelized IQ interface, use the show interfaces controller command:


user@RouterA> show interfaces controller ct1-2/3/7
Controller                                                           Admin Link
ct1-2/3/7                                                             up    up
     ds-2/3/7:1                                                        up    up
     ds-2/3/7:2                                                        up    up
# ct1-2/3/7 is the physical channelized T1 IQ interface, and ds-2/3/7:1 and ds-2/3/7:2 are the resulting  N xDS0 interfaces.
user@RouterA>  show interfaces controller ct1-2/3/8
Controller                                                           Admin Link
ct1-2/3/8                                                            up    up
t1-2/3/8                                                              up    up
# ct1-2/3/8 is the physical channelized T1 IQ interface, and t1-2/3/8 is the resulting T1 interface.

To view information about the physical channelized interface, include the ct1-fpc/pic/port option with the show interfaces command:


user@RouterA> show interfaces ct1-2/3/7
Physical interface: ct1-2/3/7, Enabled, Physical link is Up
  Interface index: 18, SNMP ifIndex: 1128, Generation: 27
  Link-level type: Controller, Clocking: Internal, Speed: T1,
  Loopback: None, Framing: ESF, Parent: None
  Device flags   : Present Running
  Interface flags: Point-To-Point SNMP-Traps 16384
  Link flags     : None
  Hold-times     : Up 0 ms, Down 0 ms
  CoS queues     : 4 supported
  Last flapped   : 2005-08-01 18:00:12 PDT (1d 00:31 ago)
  Input rate     : 0 bps (0 pps)
  Output rate    : 0 bps (0 pps)
  Statistics last cleared: Never
  DS1   alarms   : None
  DS1   defects  : None
    Line encoding: B8ZS

user@RouterA> show interfaces ct1-2/3/8
Physical interface: ct1-2/3/8, Enabled, Physical link is Up
  Interface index: 25, SNMP ifIndex: 1134, Generation: 28
  Link-level type: Controller, Clocking: Internal, Speed: T1,
  Loopback: None, Framing: ESF, Parent: None
  FCS: 16, Framing: G704, Parent: None
  Device flags   : Present Running
  Interface flags: Point-To-Point SNMP-Traps 16384
  Link flags     : None
  Hold-times     : Up 0 ms, Down 0 ms
  CoS queues     : 4 supported
  Last flapped   : 2005-08-01 18:00:11 PDT (1d 00:30 ago)
  Input rate     : 0 bps (0 pps)
  Output rate    : 0 bps (0 pps)
  Statistics last cleared: Never
  DS1   alarms   : None
  DS1   defects  : None
    Line encoding: B8ZS

To view information about an NxDS0 interface, include the ds-fpc/pic/port:channel option with the show interfaces command:


user@RouterA> show interfaces ds-2/3/7:1 detail
Physical interface: ds-2/3/7:1, Enabled, Physical link is Up
  Interface index: 73, SNMP ifIndex: 1202, Generation: 325
  Link-level type: PPP, MTU: 1504, Clocking: Internal, Speed: 64kbps, Loopback: None,
  FCS: 16, Parent: ct1-2/3/7 Interface index 18
  Device flags   : Present Running
  Interface flags: Point-To-Point SNMP-Traps 16384
  Link flags     : Keepalives
  Hold-times     : Up 0 ms, Down 0 ms
  Keepalive settings: Interval 10 seconds, Up-count 1, Down-count 3
  Keepalive statistics:
    Input : 11 (last seen 00:00:02 ago)
    Output: 10 (last sent 00:00:06 ago)
  LCP state: Opened
  NCP state: inet: Opened, inet6: Opened, iso: Opened, mpls: Not-configured
  CHAP state: Not-configured
  CoS queues     : 4 supported
  Last flapped   : 2005-08-03 12:30:37 PDT (00:10:26 ago)
  Statistics last cleared: Never
  Traffic statistics:
   Input  bytes  :                  559                   56 bps
   Output bytes  :                  656                   56 bps
   Input  packets:                   33                    0 pps
   Output packets:                   36                    0 pps
  Queue counters:       Queued packets  Transmitted packets      Dropped packets
    0 best-effort                   40                   40                    0
    1 expedited-fo                   0                    0                    0
    2 assured-forw                   0                    0                    0
    3 network-cont                   0                    0                    0
  Logical interface ds-2/3/7:1.0 (Index 36) (SNMP ifIndex 1266) (Generation 153)
    Flags: Point-To-Point SNMP-Traps Encapsulation: PPP
    Protocol inet, MTU: 1500, Generation: 352, Route table: 0
      Flags: None
      Addresses, Flags: Is-Preferred Is-Primary
        Destination: 10.25.1/24, Local: 10.25.1.2, Broadcast: 10.25.1.255,
        Generation: 445
    Protocol iso, MTU: 1500, Generation: 353, Route table: 0
      Flags: Is-Primary
    Protocol inet6, MTU: 1500, Generation: 354, Route table: 0
      Flags: Is-Primary
      Addresses, Flags: Is-Preferred
        Destination: fe80::/64, Local: fe80::2a0:a5ff:fe3d:ac6, Broadcast: Unspecified,
        Generation: 446
      Addresses, Flags: Is-Preferred Is-Primary
        Destination: feee::10:25:1:0/126, Local: feee::10:25:1:2,
        Broadcast: Unspecified, Generation: 448

To view information about a T1 or fractional T1 interface, include the t1-fpc/pic /port option with the show interfaces command. The Speed: field shows if the interface is a full T1(T1) or a fractional T1 (increments of 64 Kbps). In this case, t1-2/3/8 is a fractional T1 using two 64-Kbps time slots for a total speed of 128 Kbps.


user@RouterA> show interfaces t1-2/3/8 detail
Physical interface: t1-2/3/8, Enabled, Physical link is Up
  Interface index: 89, SNMP ifIndex: 1278, Generation: 341
  Link-level type: PPP, MTU: 1504, Clocking: Internal, Speed: 128kbps,
  Loopback: None, FCS: 16, Parent: ct1-2/3/8 Interface index 25
  Device flags   : Present Running
  Interface flags: Point-To-Point SNMP-Traps 16384
  Link flags     : Keepalives
  Hold-times     : Up 0 ms, Down 0 ms
  Keepalive settings: Interval 10 seconds, Up-count 1, Down-count 3
  Keepalive statistics:
    Input : 4 (last seen 00:00:05 ago)
    Output: 3 (last sent 00:00:09 ago)
  LCP state: Opened
  NCP state: inet: Opened, inet6: Not-configured, iso: Not-configured, mpls:
  Not-configured
  CHAP state: Not-configured
  CoS queues     : 4 supported
  Last flapped   : 2005-08-03 12:30:37 PDT (01:17:36 ago)
  Statistics last cleared: Never
  Traffic statistics:
   Input  bytes  :                  189                    0 bps
   Output bytes  :                  478                    0 bps
   Input  packets:                   13                    0 pps
   Output packets:                   28                    0 pps
  Queue counters:       Queued packets  Transmitted packets      Dropped packets
    0 best-effort                   28                   28                    0
    1 expedited-fo                   0                    0                    0
    2 assured-forw                   0                    0                    0
    3 network-cont                   0                    0                    0
  DS1   alarms   : None
  DS1   defects  : None
  Logical interface t1-2/3/8.0 (Index 52) (SNMP ifIndex 1279) (Generation 169)
    Flags: Point-To-Point SNMP-Traps Encapsulation: PPP
    Protocol inet, MTU: 1500, Generation: 401, Route table: 0
      Flags: None
      Addresses, Flags: Is-Preferred Is-Primary
        Destination: 10.255.126/24, Local: 10.255.126.2,
        Broadcast: 10.255.126.255, Generation: 525

Published: 2010-04-15