Advanced Router Configuration

ACRC Test Objective: The E series recommends telephone network standards (E.163 specifies the international telephone numbering plan and E.164 specifies the international ISDN addressing). I standards deal with concepts, terminology, and general methods (I.100 specifies concepts, structures, and terminology and I.400 specifies user-network interfaces). The Q-Series recommends switching and signaling (Q.921 is for LAPD and Q.931 is for ISDN network layer between the terminal and switch).

ACRC Test Objective 48: Describe the components that make up ISDN connectivity. The ISDN interface can only allow a single encapsulation type although it can multiplex packets from several higher-layer protocols. By default, it uses HDLC but you can configure it to use PPP and with PPP you can also enable CHAP.

The correct answer is NT1 (Network Termination 1). NT2 is the point where all ISDN lines at a site are combined and switched. TE1 is the Terminal Endpoint 1 and designates a router as a device having a native ISDN interface. TE2 designates a router that requires a TA for its BRI signals. TA is a Terminal Adapter that converts EIA/TIA-232, V.35, and other signals into BRI signals.

ACRC Test Objective 48: Describe the components that make up ISDN connectivity. The correct answer is T. The T reference is electrically identical to the S interface. It references the outbound connection from the NT2 to the ISDN network. S references the points that connect into the NT2. It enables calls between various customer premises equipment.

ACRC Test Objective 49: Configure ISDN BRI. Your router is a TE1, which has the TA function built in. If you did not have an interface labeled BRI then your router has a nonnative ISDN interface is a TE2. You would need to obtain and external TA device and attach it to the serial interface.

ACRC Test Objective 49: Configure ISDN BRI. If you did not have an interface labeled BRI then your router has a nonnative ISDN interface is a TE2. You would need to obtain and external TA device and attach it to the serial interface.

ACRC Test Objective 48: Describe the components that make up ISDN connectivity. AT&T 5ess and 4ess and Northern Telecom DMS-100 are common in the United States and Canada. VN2 and VN3 are common in France. Net3 and Net5 is common in the United Kingdom. NTT is common in Japan.

ACRC Test Objective 49: Configure ISDN BRI. It specifies the switch type for AT&T basic rate switches. "isdn switch-type basic-dms100" specifies the switch type for Northern Telecom basic rate switches. "isdn switch-type basic-ni1" specifies the switch type for National ISDN-1 basic rate switches. Other switch types are basic-1tr6 for German 1TR6, basic-ts013 for Australian TS013, basic-net3 for the United Kingdom and Europe, ntt for NTT ISDN in Japan, and none for a specific switch specified.

You will need to configure two numbers: one for each B channel.

Configure Legacy dial-on-demand routing (DDR). The syntax is dialer map protocol next-hop-address [name hostname] [speed 56 | 64] [broadcast] dialer-string. "dialer map ip 10.1.0.2 name router1 5551000" is the correct command.

The load threshold is a ratio where 255 would represent 100% of the bandwidth. Possible numbers are from 1 to 255.

"show isdn status" will give you ISDN connection statistics. "show dialer" displays general diagnostic information. "show isdn active" shows the active connection and the number called. "show ip route" displays static and dynamic routes.

"debug q921" verifies your ISDN connection. Other troubleshooting commands are "debug dialer" to find out information such as what number is being dialed and "clear interface" to clear a call that is in progress.

DDR (Dial-on-demand Routing) establishes a connection when a specific type of traffic initiates a call or when you need a backup link. The circuit-switched calls are placed using PSTN or ISDN.

Cisco offers a range of products including some routers with native ISDN interfaces. Multiple bearer channels, screening incoming calls, multiprotocols supported, SNMP management, and MultiLink PPP encapsulation are supported. Using DDR provides for reduced cost by programming the router to connect when it finds interesting traffic. DDR provides dedicated connectivity only for the length of the required session but it is not used for continuous connectivity.

Configure ISDN BRI. The spid number identifies the subscribed service. This number is assigned by the ISDN service provider. The ldn is optional and is a local dial number.

E.163 is used for International Telephone Numbering Plan and E.164 is used for International ISDN addressing.

100 series is used for concepts, structures and terminology. I.400 Series is used for UNIs.

Q.921 is used for LAPD on the D channel. Q.931 is used for ISDN network layer between terminal and switch.

BRI has two 64 kbps bearer channels plus one 46 kbps data channel. BRI connects to an NT1. PRI is available in North America and Japan. It has 23 bearer channels and one 64 kbps D channel. In Europe PRI has a 30 B channel and one D channel.

Configure dialer profiles. · Specify interesting traffic. dialer-list 1 protocol ip permit · Define static routes. ip route 17.1.0.0 255.255.255.0 Dialer 17.1.0.1 · Create the dialer interface. interface Dialer ip address 17.1.0.2 255.255.255.0 encapsulation ppp, dialer remote-name p1r2, dialer string 5552000 class top1r2, dialer pool 4, dialer-group 1, ppp authentication chap no ip address, encapsulation ppp, dialer pool-member 4 priority 255, no fair-queue, ppp authentication chap · Optional: Define the map class. map-class dialer top1r2, dialer idle-timeout 180, dialer isdn speed 56.

Describe the components that make up ISDN connectivity. TE1 is used to designate a router as a device having native ISDN interface. NT2 is for ISDN lines at the customer site which are switched using a customer switch. TE2 is used to designate a router as a device needing a TA for BRI signals. TA is used to convert EIA/TIA-232, V.35 signals into BRI signals.

Describe the components that make up ISDN connectivity. BRI has two 64 kbps bearer channels plus one 46 kbps data channel. BRI connects to an NT1. PRI is available in North America and Japan. It has 23 bearer channels and one 64 kbps D channel. In Europe PRI has a 30 B channel and one D channel.

The LT (Local Termination) is the portion of the local exchange that terminates the local loop. The ET (Exchange Termination) is the portion of the exchange that communicates with other ISDN components.

S provides references to the points that connect into the NT2. R is the point that references between a non-ISDN compatible device and terminal adapter. T is the same as s, it references outbound connections form the NT2. U references the connection between NT1 and ISDN owned by the phone company.

France uses VN2 and VN3. Japan uses NTT. United Kingdom uses Net3 and Net5.

The following commands work: int s0 backup interface serial 1 backup load 70 10 This tells the router to activate the secondary line when the load reaches 70% and to deactivate it when it returns to 10%.