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Cisco 700 series routers connect Ethernet LANs to other networks over Integrated Services Digital Network (ISDN) Basic Rate Interface (BRI) lines.
Cisco 700 series routers offer multiprotocol routing capability between WAN and LAN ports and can function as transparent bridges.
This section describes the major features of Cisco 700 series routers.
The CiscoSecure Authentication Agent (available for Windows 95 and Windows NT 4.0) application simplifies the use of token authentication over ISDN. There are two authentication modes: single authentication and double authentication.
The Cisco 700 series router operates in single authentication mode when Token Authentication Support (TAS) is enabled. The CiscoSecure Authentication Agent is available on the Cisco Website.
Cisco 700 series router software Release 4.0(1) and higher supports the Cisco 700 Fast Step software. Cisco 700 Fast Step software simplifies the setup, configuration, and monitoring of Cisco 700 series routers.
Cisco 700 Fast Step runs on Microsoft Windows 95, Windows 98, and Windows NT systems. It is provided with your router on the Cisco Fast Step CD-ROM. The application is also available on Cisco Connection Online (CCO).
The D channel is an always-available, packet-oriented link between the remote office and the central office. The customer premises equipment (CPE) can use the D channel to pass Multilink Point-to-Point Protocol (PPP) and Transaction Control Protocol and Internet Protocol (TCP/IP) encapsulated in X.25. The D-channel X.25 packets are handled at the central office by the X.25 packet handler, so these packets can be routed without crossing the circuit-switched switch fabric.
When D-channel bandwidth exceeds a defined threshold, the router places one or more ISDN B-channel calls to increase bandwidth. When bandwidth requirements fall below a defined threshold, the B channels are released.
A maximum of four switched virtual circuits (SVCs) can be used for AO/DI. If a D-channel connection is not available, the router uses the first available B channel for a call. After the D channel PPP link is established, it is not torn down. If Bandwidth Allocation Control Protocol (BACP) is configured, Bandwidth on Demand (BOD) is negotiated by using BACP.
Performance of the multilink protocol declines when the bandwidth of the underlying links varies widely; therefore, the router idles the D channel when the B channels are in use. (RFC 1990 describes how packets can be redirected using the multilink procedure.) After the number of links drops to one and that link is idle, the router returns to normal operation.
With Cisco 700 series router software Release 4.2(2), you can specify the lease time for all the addresses. (The previous Cisco 700 series router DHCP server implementation assigned an IP address to the DHCP client with an infinite lease time.)
There are two modes of operation in the Controller PAD (TPAD) implementation that respond to the enhanced point-of-sale system (EPOS), Verbose and Terse. In Verbose mode, the response is in strings, such as "CONNECT," "NO CARRIER," "BUSY," and so forth. In Terse mode the response is in numbers, such as 1 (CONNECT), 3 (DISCONNECT), 7 (BUSY), and so forth. In addition, in software Release 4.3.1, a series of TPAD commands have been implemented to support RIVA functionality.
In areas served by carriers providing flat-rate ISDN service, the lines can be permanently connected between the router and the central office switch. This feature can work on any switch type.
The automatic configuration feature allows the Cisco 700 series router to obtain a configuration file from a remote server using Bootstrap Protocol (BOOTP).
The automatic service profile identifier (SPID) and switch detection simplifies the use of ISDN terminal equipment and makes the equipment easier to use with fewer parameters to enter. With this feature, you only enter the local directory numbers with area code; no SPID number or switch type is required.
The automatic detection feature only applies to ISDN switches for the USA and Canada, usually an AT&T 5ESS Custom, DMS-100, NI-1, or NI-2 switch. The automatic detection mechanism might not work with any other switch, such as a Siemens switch. The automatic detection feature is only implemented in the U. S. image.
The Bandwidth Allocation Control Protocol (BACP) and the Bandwidth Allocation Protocol (BAP) define a set of rules to control dynamic bandwidth allocation to coordinate and negotiate the actual allocation and deallocation of the second channel.
If spoofing is set, the router keeps a local database of up to 100 Domain Name System (DNS) name entries and has an aging scheme to age out the unused name entries. When a WINS client sends out a NetBIOS Name query, the router can attempt to answer the query in place of the WINS server. If the router cannot answer, the router forwards the query packets to the server, which provides the response to the client.
DHCP automates IP addressing and reduces the number of IP addresses a site might require. Cisco 700 series routers can function as a dynamic host configuration protocol (DHCP) server.
Cisco 700 series routers can also function as a DHCP relay agent, but the router cannot act as a DHCP server and a relay agent at the same time. When configured, your router can relay DHCP requests and responses between DHCP clients and a specified DHCP server.
Cisco 700 series routers support port address translation (PAT) allowing a designated private IP network to communicate with the outside world. When configured, Cisco 700 series routers translate source addresses from an IP private network to a single, global, unique IP address before forwarding the packets to the outside world.
The router can be assigned an IP address from the remote device using Internet Protocol Control Protocol (IPCP) address negotiation. The implementation is based on RFC 1332, and it supports IPCP options 1 and 3. (It does not support option 2, TCP/IP Header Compression.) IP unnumbered is also supported. IPCP address negotiation is on by default in any profile configured for IP routing. This feature does not support address assignment to remote devices.
Cisco 700 series routers support data compression using the compression algorithm QIC-122 standard, Stacker LZS. Data compression is a software configuration option that optimizes the ISDN line bandwidth. Packets are compressed before being sent to the ISDN line. After they arrive at their destination, the packets are decompressed and sent to the remote LAN.
Fee Pulse Mode manages the ISDN connection based on the paid periods of time. If other thresholds indicate a call should be dropped due to low traffic, Fee Pulse Mode maintains the connection until the current paid period has expired. Therefore, you are not paying full price for part of a connection period. This feature is available only for NET3 (same as ETSI) switch types, and you must subscribe to Advice of Charge-During Active Call (AOC-D) supplementary service.
If the feature is enabled and idle time expires, the router checks the remaining time in the current paid period. The router maintains the connection until the end of the paid period, minus the disconnect time required to terminate the PPP and ISDN links.
If the idle time expires too close to the end of the paid period to close the connections before the end of the paid period, the router extends the connection to the end of the next paid period, minus disconnect time.
Cisco 700 series router software Release 4.1(1) and higher includes a special image that supports the Cardway TPAD services (British Telecom). The connection is made through the Cisco 700 series router serial port.
Priority queueing improves the responsiveness of the D channel link. X.25 is a flow-controlled, nonbroadcast multiaccess (NBMA) protocol. A high-priority packet might not be transmitted first, even when it is eligible. With priority queueing, data can be put into one of the four priority queues: high, medium, normal, and low. Packets with the same priority are sent on a first-in-first-out basis.
In software Release 4.0(1) and higher, the authentication sequence is no longer required for leased line connections. (For 64-kbps or 128-kbps leased line connections, previous versions of the software required PAP/CHAP authentication to identify the corresponding profile.)
To eliminate the need for authentication, a user-defined profile named leasedline must be present and defined. If this profile is not present upon call connect, the router requires authentication to select the correct profile. If the call cannot be authenticated, the router defaults to the Standard profile. Within the user-defined profile called leasedline, verify that PPP authentication is set to none. The switch types that support this feature are PERM64 and PERM128.
Cisco 700 series routers provide the following security features:
Cisco 700 series routers support Simple Network Management Protocol (SNMP).
Cisco 700 series routers support the following SNMP community names:
These community names are read-only and cannot be changed. Cisco 700 series routers do not support SNMP set commands.
Cisco 700 series routers support the following SNMP Management Information Bases (MIBs):
Cisco 700 series routers support MIB II standards as follows:
Cisco 700 series routers support IEEE 802.1d MIB standards as follows:
Cisco 700 series routers support the following Request For Comments (RFC) documents:
Figure 1-1 shows the front panel of a Cisco 700 series router.
The LEDs on the front panel of Cisco 700 series routers display the activity status of the router as connections are made and as packets are sent and received. Figure 1-2 and Figure 1-3 illustrate the LEDs on the front panels of Cisco 700 series routers.
Table 1-1 lists the LEDs and their functions.
| LED | Function |
|---|---|
Indicates the router operating status. On when power is supplied to the router, the router passes the self-test, and is operating normally. | |
NT1 |
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On when the NT1 S interface and the ISDN terminal device(s) are synchronized. Also indicates framing between the router and the ISDN switch. | |
On when packets have been sent to or received from the Ethernet within the last minute. | |
RXD | Blinks when packets are received from the LAN. |
Blinks when packets are sent to the LAN. | |
On when the first LAN link of the unmanaged hub is connected. Blinks (once every 1.5 seconds) when there is a problem with the connection. | |
On when there is a connection on the second LAN link of the unmanaged hub is connected. Blinks (once every 1.5 seconds) when there is a problem with the connection. | |
On when there is a connection on the third LAN link of the unmanaged hub is connected. Blinks (once every 1.5 seconds) when there is a problem with the connection. | |
On when there is a connection on the fourth LAN link of the unmanaged hub is connected. Blinks (once every 1.5 seconds) when there is a problem with the connection. | |
Blinks when a call is establishing a connection on the first B channel. On when a call is established or the connection has not yet timed out. | |
CH1 RXD | Blinks when packets are received on the first B channel. |
CH1 TXD | Blinks when packets are sent on the first B channel. |
Blinks when a call is establishing a connection on the second B channel. On when a call is established or the connection has not yet timed out. | |
CH2 RXD | Blinks when packets are received on the second B channel. |
CH2 TXD | Blinks when packets are sent on the second B channel. |
PH 1 |
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The data call button on the front panel of Cisco 770 series routers provides an alternative to establishing or disconnecting data calls through the command interface. The data call button performs in Make or Break mode. If no B channels are connected for data, and at least one B channel is available, the button works in Make mode and attempts to establish a call. When at least one B channel is connected for data, the button works in Break mode, disconnecting the call. Table 1-2 summarizes the operation of the Cisco 770 series data call button.
| Current Status | Data Call Button Operation |
|---|---|
No call up | Make a data call |
1 data call only | Disconnect the data call |
2 data calls | Disconnect both data calls |
1 voice call only | Make a data call |
2 voice calls | No action |
1 data and 1 voice call | Disconnect the data call |
All Cisco 700 series routers include a DB-9F configuration port. Table 1-3 lists the network interfaces available on each router by model number.
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| Model | Interfaces |
|---|---|
Cisco 761 | 1 Ethernet and 1 ISDN BRI S/T |
Cisco 762 | 1 Ethernet, 1 ISDN BRI S/T, and 1 ISDN BRI U |
Cisco 765 | 1 Ethernet, 1 ISDN BRI S/T, and 2 analog telephone |
Cisco 766 | 1 Ethernet, 1 ISDN BRI S/T, 1 ISDN BRI U, and 2 analog telephone |
Cisco 771 | 4-port unmanaged Ethernet hub and 1 ISDN BRI S/T |
Cisco 772 | 4-port unmanaged Ethernet hub, 1 ISDN BRI S/T, and 1 ISDN BRI U |
Cisco 775 | 4-port unmanaged Ethernet hub, 1 ISDN BRI S/T, and 2 analog telephone |
Cisco 776 | 4-port unmanaged Ethernet hub, 1 ISDN BRI S/T, 1 ISDN BRI U, and 2 analog telephone |
The rear panels of Cisco 760 series routers are shown in Figure 1-4 through Figure 1-7. Cisco 770 series routers are shown in Figure 1-8 through Figure 1-11.
Posted: Tue Feb 23 14:19:44 PST 1999
Copyright 1989-1999©Cisco Systems Inc.