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This chapter describes the PA-MC-T3 and contains the following sections:
The PA-MC-T3 is a single-width port adapter that provides one T3 interface connection using BNC connectors. (See Figure 1-1.) The interface can provide up to 28 T1 lines (a single T3 group). Each T1 line is presented to the system as a serial interface that can be configured individually.
The PA-MC-T3 T3 link is channelized into 28 independent T1 data lines. Each T1 line can be unchannelized or channelized for serial transmission of data.
Each of the T1 lines can use the whole T1 bandwidth, a portion of the T1 bandwidth, or the T1 bandwidth in channelized form for data transmission. Usable bandwidths for each T1 line are n x 56 kbps or n x 64 kbps, where n is a number representing timeslots 1 to 24. Channelized T1 allows up to 24 timeslots (56 kbps/64 kbps) per T1 line. The unused portion of the T1 bandwidth, when not running at full T1 speeds, cannot be used and is filled with idle channel data. Aggregation of multiple T1 lines is not supported. The PA-MC-T3 can support a maximum of 128 logical channels.
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Note T1 lines on the PA-MC-T3 are numbered 1 to 28 instead of the more traditional zero-based scheme (0 to 27) used with other Cisco products. This is to ensure consistency with telco numbering schemes for T1 lines within channelized (multi-channel) T3 equipment. |
The T3 section of the PA-MC-T3 supports the maintenance data link channel (when using c-bit parity) as well as payload and network loopbacks. The T1 section of the PA-MC-T3 supports facilities data link (FDL) in Extended Superframe (ESF) framing, as well as various loopbacks. Bit error rate testing (BERT) is supported on each of the T1 lines. BERT is typically done over an unframed T1 signal.
The PA-MC-T3 supports Cisco High-Level Data Link Control (HDLC), Frame Relay, PPP, and SMDS Data Exchange Interface (DXI) encapsulations over each T1 link. For Switched Meultimegabit Data Service (SMDS) only, DXI is sent on the T1 line, so it needs to connect to an SMDS switch that has direct DXI input.
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Note The PA-MC-T3 does not support the aggregation of multiple T1 lines (called inverse multiplexing, or bonding) for higher bandwidth data rates. |
The physical T3 link on the PA-MC-T3 consists of two female BNC connectors, one for receive (RX) and one for transmit (TX). You must use 75-ohm RG-59 coaxial interface cables with male BNC connectors to connect the PA-MC-T3 interface with external T3 equipment. (For cable information, refer to the "Cables, Connectors, and Pinouts" section.)
Any of the 28 T1 lines can be configured as channelized T1 lines. You can group the timeslots in these T1 lines into several individual logical channel groups, each of which carries data with different data-link layer protocol encapsulations.
Each logical channel group can be composed of individual 56-kbps or 64-kbps timeslots, or individual timeslots plus ranges of timeslots; for example, a channel group might be composed of timeslots 1, 9, and 12-14. Each logical channel group can contain from 1 to 24 timeslots maximum; the same time slot cannot be used in more than one logical channel group. Any unused timeslots are filled with programmable idle-channel data.
Each T1 line contains onboard T1 bit error rate test (BERT) circuitry. With this, the port adapter software can send and detect programmable patterns, and you can run a BER test on any T1 line or all of the 28 T1 lines simultaneously.
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Note Onboard T3 BER testing is not supported. |
The PA-MC-T3 contains the following features:
The PA-MC-T3 T3 port is designed to receive and transmit at the DSX-3 level while driving and receiving from a 75-ohm coaxial cable (ATT 728A type coax). The T3 port connects directly to any equipment with DSX-3 level BNC connectors.
lists the specifications the T3 front end is designed to meet.
| Parameter | Specification |
|---|---|
Line rate | 44.736 Mbps (±20 ppm) |
Line code | B3ZS (bipolar with three-zero substitution) |
Impedance | 75 ohms |
Pulse shape | ANSI T1.102, pulse amplitude is between 0.36 and 0.85 volts (V) peak |
Input signal | DSX-3 (9.7 dB to -11.8 dB) |
Output signal | DSX-3, able to drive 450 feet (135 meters) of 75-ohm coaxial cable (728A or equivalent) and meet pulse shape template at the line side |
The PA-MC-T3 has one row of six status LEDs and one enabled LED. (See Figure 1-2.)
After system initialization, the enabled LED goes on to indicate that the port adapter is enabled for operation.
The following conditions must be met before the PA-MC-T3 is enabled:
If any of the above conditions are not met, or if the initialization fails for other reasons, the enabled LED does not go on.
Table 1-1 lists port LED colors and indications.
| LED Label | Color | State | Meaning |
ENABLED | Green | On | Port adapter is enabled for operation. |
ALARM | Yellow | On | An alarm condition1 is received on any configured T1 line or the T3 link. |
Blinking | A port adapter boot failure has occurred.2 | ||
LOOP | Yellow | On | A T1 line or the T3 link is in a loopback state and is not enabled for normal data traffic. |
LOS | Yellow | On | A loss of the received signal on the T3 link is detected by the line interface unit (LIU) on the port adapter. |
OOF | Yellow | On | A DS3 out-of-frame condition. |
AIS | Yellow | On | An alarm indication signal is received on the T3 link. |
FERF | Yellow | On | A far-end receive failure signal is detected by the receiver.3 |
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Note In addition to the interface status information provided by the LEDs, you can also retrieve detailed interface status information either through the router's console port or through Telnet or Simple Network Management Protocol (SNMP). |
The interface connectors on the PA-MC-T3 are RG-59 coaxial BNC types, with one connector and cable for transmit (TX) and one for receive (RX). The BNC connectors are transformer-coupled to the PA-MC-T3 line interface unit (LIU), which is the analog physical interface on the PA-MC-T3.
The pinout and signal descriptions for the BNC connectors on the PA-MC-T3 are as follows:
You must install a ferrite sleeve (also called a common-mode choke) on each 75-ohm coaxial cable to reduce the effects of electromagnetic interference (EMI). (Cisco Systems supplies two ferrite sleeves with your PA-MC-T3, one for each of the two 75-ohm coaxial cables.)
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Note You must attach the ferrite sleeve on the end of each coaxial cable, nearest the PA-MC-T3, as close to the BNC connector as possible. (See .) |
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Caution The ferrite sleeve prevents electromagnetic interference (EMI) from affecting the T3-equipped system and is a required component for proper system operation. |
shows the typical 75-ohm RG-59 coaxial cable pair that you supply and should use with the PA-MC-T3. Use only this type of coaxial cable pair for your PA-MC-T3 connections. Use one 75-ohm coaxial cable for each PA-MC-T3 connection: RX and TX.
We strongly recommend that you fasten together your transmit and receive cables along their entire length, as shown in , which reduces the effects of EMI. You can use standard heat-activated shrink tubing or cable ties for this purpose.
You can also order from Cisco Systems a 75-ohm coaxial cable pair with ferrite beads attached (as Cisco Product Number CAB-ATM-DS3/E3). (See Figure 1-5). This 75-ohm coaxial cable pair is not available from outside commercial cable vendors.
The Catalyst RSM/VIP2 can be installed in any slot except the top slots, which contain the supervisor engine modules. The Catalyst RSM/VIP2 in a Catalyst 5000 family switch does not use interface processor slot numbering; therefore, slots are not numbered in Figure 1-6. The PA-MC-T3 can be installed into either port adapter slot 0 or 1 on a Catalyst RSM/VIP2. Figure 1-6shows a Catalyst RSM/VIP2 with two port adapters installed.
Figure 1-7 shows a Cisco 7206 with port adapters installed. In the Cisco 7206 (including the Cisco 7206 and Cisco 7206VXR as router shelves in a Cisco AS5800 Universal Access Server), port adapter slot 1 is in the lower left position, and port adapter slot 6 is in the upper right position. (The Cisco 7202 and Cisco 7204 are not shown; however, the PA-MC-T3 can be installed in any available port adapter slot.)
Figure 1-8 shows the slot numbering of port adapters in a Cisco uBR7246 series router. The port adapter slots are numbered slot 1 and slot 2 for the Cisco uBR7246 and slot 1 for the Cisco uBR7223. (Slot 0 is always reserved for the Fast Ethernet port on the I/O controller---if present.)
Figure 1-9 shows a VIP2-15 or VIP2-40 with installed port adapters. With the VIP2 oriented as shown in Figure 1-9, the left port adapter is in port adapter slot 0, and the right port adapter is in port adapter slot 1. The slot numbering is the same for the Catalyst RSM/VIP2-15 and VIP2-40. The left port adapter is port adapter slot 0, and the right port adapter is port adapter slot 1. The slots are always numbered 0 and 1.
Figure 1-10 shows a VIP4 with installed port adapters. With the VIP4 oriented as shown, the left port adapter is in port adapter slot 0, and the right port adapter is in port adapter slot 1.
In the Cisco 7000, Cisco 7507, Cisco 7513, and Cisco 7576 chassis, the VIP4 is installed vertically. In the Cisco 7010 and Cisco 7505 chassis, the VIP4 is installed horizontally.
This section describes how to identify interface addresses for the PA-MC-T3 in supported platforms. Interface addresses specify the actual physical location of each interface on a router or switch.
Interfaces on the PA-MC-T3 installed in a router maintain the same address regardless of whether other port adapters are installed or removed. However, when you move a port adapter to a different slot, the first number in the interface address changes to reflect the new port adapter slot number.
Interfaces on a PA-MC-T3 installed in a VIP maintain the same address regardless of whether other interface processors are installed or removed. However, when you move a VIP to a different slot, the interface processor slot number changes to reflect the new interface processor slot.
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Note The Cisco IOS software recognizes a configured logical channel group as a serial interface; therefore, you can use all configuration commands that are available for serial interfaces with configured logical channel groups. You can configure a logical channel group to carry data traffic using the following encapsulation methods: PPP, HDLC, SMDS, and Frame Relay. Set the encapsulation method you want using the serial interface configuration commands. For configured logical channel groups, you can use all command switches that apply to a serial interface (including optimum switching). |
Table 1-3 explains how to identify interface addresses.
| Platform | Interface Address Format | Numbers | Syntax |
|---|---|---|---|
Catalyst RSM/VIP2 in | Port-adapter-slot-number/interface-port-number/ | Port adapter slot---always 0 or 1 Interface port---0 T1 line number---1 through 28 Logical channel group on the T1 line---0 through 23 | 0/0/1/0 |
Cisco 7200 series routers | Port-adapter-slot-number/interface-port-number/ | Port adapter slot---0 through 6 (depends on the number of slots in the router)1 Interface port---0 T1 line number---1 through 28 Logical channel group on the T1 line---0 through 23
| 1/0/1/0 |
Cisco uBR7223 router | Port-adapter-slot-number/interface-port-number
| Port adapter slot---always 11 Interface port---0 T1 line number---1 through 28 Logical channel group on the T1 line---0 through 23
| 1/0/1/0 |
Cisco uBR7246 router | Port-adapter-slot-number/interface-port-number
| Port adapter slot---always 1 or 21 Interface port---0 T1 line number---1 through 28 Logical channel group on the T1 line---0 through 23
| 1/0/1/0 |
VIP2 or VIP4 in Cisco 7000 series or | Interface-processor-slot-number/port-adapter-slot | Interface processor slot---0 through 12 (depends on the number of slots in the router) Port adapter slot---always 0 or 1 Interface port---0 T1 line number---1 through 28 Logical channel group on the T1 line---0 through 23 | 3/1/0/1/0 |
| 1Port adapter slot 0 is reserved for the Fast Ethernet port on the I/O controller (if present). |
This section describes how to identify the interface addresses used for the PA-MC-T3 on the Catalyst RSM/VIP2 in Catalyst 5000 family switches. The interface address is composed of a four-part number in the format port-adapter-slot number/interface-port number/t1-line-number:channel-group-number.
The first number identifies the interface processor slot on the Catalyst RSM/VIP2 and is either 0 or 1.
The second number identifies the interface port on the PA-MC-T3, which is always 0.
The third number identifies the T1 line number on the PA-MC-T3 and is a number from 0 through 28.
The fourth number identifies the logical channel group on the T1 line and is a number from 0 through 23.
The PA-MC-T3 can be installed in either port adapter slot 0 or slot 1. Figure 1-11 shows two PA-MC-T3s installed in port adapter slots 0 and 1 on a Catalyst RSM/VIP2-40.
See Table 1-3 for the interface address format.
This section describes how to identify the interface addresses used for the PA-MC-T3 in Cisco 7200 series series routers or Cisco uBR7200 series routers. The interface address is composed of a four-part number in the format port-adapter-slot-number/interface-port-number/t1-line-number:channel-group-number. See Table 1-3 for the interface address format.
In Cisco 7200 series routers, port adapter slots are numbered from the lower left to the upper right, beginning with port adapter slot 1 and continuing through port adapter slot 2 for the Cisco 7202, slot 4 for the Cisco 7204 and Cisco 7204VXR, and slot 6 for the Cisco 7206 and Cisco 7206VXR. (Port adapter slot 0 is reserved for the optional Fast Ethernet port on the I/O controller---if present.) Figure 1-12 shows a PA-MC-T3 in port adapter slot 3 of the Cisco 7206 router.
The interface address of the interface on the PA-MC-T3 in port adapter slot 1 is
1/0/1/0. If the PA-MC-T3 was in port adapter slot 4, this same interface would be numbered 4/0/1/0 (port adapter slot 4, interface 0, T1 line number 1 and logical channel group number 0).
Figure 1-13 shows a PA-MC-T3 installed in slot 2 of a Cisco uBR7246 router. The port adapter slots are numbered slot 1 and slot 2 for the Cisco uBR7246 and slot 1 for the Cisco uBR7223. (Slot 0 is always reserved for the Fast Ethernet port on the I/O controller---if present.) The interface port number is always 0.
2---Cisco uBR7246 Shown
The interface address of the interface on a PA-MC-T3 in port adapter slot 2 is 2/0/1/0 (port adapter slot 2, interface 0, T1 line number 1 and channel group number 0). If the PA-MC-T3 was in port adapter slot 1, this same interface would be numbered 1/0/1/0 (port adapter slot 1 and interface 0, T1 line number 1 and channel group number 0).
This section describes how to identify the interface addresses used for the PA-MC-T3 on a VIP in Cisco 7000 series and Cisco 7500 series routers.
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Note Although the processor slots in the 7-slot Cisco 7000 and Cisco 7507 and 13-slot Cisco 7513 and Cisco 7576 are vertically oriented and those in the 5-slot Cisco 7010 and Cisco 7505 are horizontally oriented, all Cisco 7000 series and Cisco 7500 series routers use the same method for slot and port numbering. |
See Table 1-3 for the interface address format. The interface address is composed of a five-part number in the format interface-processor-slot-number/port-adapter-slot-number/interface-port- number/t1-line-number:channel-group-number.
Figure 1-14 shows a sample Cisco 7505 system. The interface address of the PA-MC-T3 is 3/1/0/1/0 (interface processor slot 3, port adapter slot 1, interface 0, T1 line number 1, channel group number 0). If the port adapter was in port adapter slot 0 on the VIP, this same interface address would be numbered 3/0/0/1/0.
Posted: Fri Apr 28 10:12:23 PDT 2000
Copyright 1989 - 2000©Cisco Systems Inc.
