© Synergon Informatika Rt., 1999 Chapter 16 Configuring Bandwidth on Demand

2 Objectives Upon completion of this chapter, you will be able to perform the following tasks: Configure dial-on-demand routing (DDR) Configure DDR using access lists Configure PPP authentication Configure DDR rotary group Configure IPX over DDR Configure snapshot routing Configure dial backup

3 Bandwidth on Demand Overview Primary Backup Dial-on-Demand Routing Dial Backup

4 Dial-on-Demand Routing Configuration

5 Dial-on-Demand Overview Synchronize Database Orders are Are Placed Manufacturing and Shipping Headquarters Transaction processing using DDR Publish Confirmations

6 Dial-on-Demand Routing Use ISDN or PSTN Use for low-volume, periodic traffic Connect remote sites only when traffic dictates

7 DDR Operation ISDN or Basic Service Interesting packets dictate DDR call User dictates what is interesting After idle period, call disconnected “Interesting” packet arrives DCE Dial connection

8 DDR Configuration Tasks 1 Define interesting traffic 2 Enable DDR on an interface 3 Assign traffic definition to an interface 4 Define destination(s) 5 Configure call parameters 1 Define interesting traffic 2 Enable DDR on an interface 3 Assign traffic definition to an interface 4 Define destination(s) 5 Configure call parameters DDR Destination DDR call parameters DDR call parameters S0/B0 Dialer group Dialer List

9 DDR Commands Router (config) # dialer-list dialer-group protocol protocol-name [ permit | deny | list access-list-number ]  Defines “interesting” packets for DDR  Assigns an access list to dialer group Router (config) # dialer-list dialer-group list access-list-number Assigns an access list to a dialer group Router (config-if) # dialer in-band Enables DDR on an interface Not required for ISDN BRI

10 DDR Commands (cont.) Router (config-if) # dialer-group group-number  Assigns an interface to dialer access group Router (config-if) # dialer map protocol next-hop-address [ name hostname ] [ speed 56| 64 ] [ broadcast ] [ dialer-string ] Defines how to reach a destination Router (config-if) # dialer string string-number Specifies the telephone number to be called for interfaces calling a single site

11 DDR Optional Commands Router (config-if) # dialer-load-threshold load [ outbound | inbound | either ] Sets maximum load before dialing additional calls Router (config-if) # dialer idle-timeout seconds Establishes the idle time before disconnect Router (config-if) # dialer fast-idle seconds Establishes idle time when line contention exists

12 DDR Example BR0 ISDNA B (Number to reach) Traffic for subnets 12 and 14 of network will trigger a DDR call E0

13 DDR Example (cont.) isdn switch-type basic-net3 ip route ip route dialer-list 1 protocol ip permit ! interface bri 0 encapsulation ppp ip address dialer-group 1 ! dialer map ip ! dialer idle-timeout 300 isdn switch-type basic-net3 ip route ip route dialer-list 1 protocol ip permit ! interface bri 0 encapsulation ppp ip address dialer-group 1 ! dialer map ip ! dialer idle-timeout 300 Define static routes on Cisco A to reach networks on Cisco B Protocol list identifies interesting packets Interface configuration for DDR Setup details for router and the dealing device Time to wait for more traffic before DDR drops call Subnets BR0 ISDNA B BR0

14 DDR Using Access Lists Overview Telnet ISDNA B IP Initiates DDR call Does not Access lists allow individual protocols to be defined as interesting (Telnet)

15 DDR Example BR0 ISDNA B BR IP FTP traffic for subnets 12 and 14 of network will trigger a DDR call IGRP routing updates and ping will not trigger a DDR call E0

16 DDR/Access List Example (cont.) access-list 101 deny igrp any access-list 101 deny icmp any echo access-list 101 permit tcp any eq ftp dialer-list 1 list 101 ! ip route ip route ! interface bri 0 ip address dialer-group 1 dialer map ip ! dialer idle-timeout 300 ] access-list 101 deny igrp any access-list 101 deny icmp any echo access-list 101 permit tcp any eq ftp dialer-list 1 list 101 ! ip route ip route ! interface bri 0 ip address dialer-group 1 dialer map ip ! dialer idle-timeout 300 ] Access list defining interesting packets on Cisco A Static routes to reach destination Interface configuration DDR Time to wait before call Subnets BR0 ISDNA B BR0

17 Verifying DDR Configuration Home-isdn-router # show dialer interface b 0 BRI0 - dialer type = ISDN Dial StringSuccess FailuresLast calledLast status 01:10:43successful 0 incoming call(s) have been screened. Time until disconnect 116 secs Current call connected 00:10:44 BRI0: B-Channel 2 Idle timer (120 secs), Fast idle timer (20 secs) Wait for carrier (30 secs), Re-enable (15 secs) Home-isdn-router # show dialer interface b 0 BRI0 - dialer type = ISDN Dial StringSuccess FailuresLast calledLast status 01:10:43successful 0 incoming call(s) have been screened. Time until disconnect 116 secs Current call connected 00:10:44 BRI0: B-Channel 2 Idle timer (120 secs), Fast idle timer (20 secs) Wait for carrier (30 secs), Re-enable (15 secs) BRI0: B-Channel 1 Idle timer (120 secs), Fast idle timer (20 secs) Wait for carrier (30 secs), Re-enable (15 secs) Connected to (central-site-router1) Shows DDR interface diagnostics

18 Scalable DDR Configuration

19 Scalable DDR Configuration Topics l Configuring PPP authentication l Dialing multiple simultaneous destinations using a rotary group l Configuring DDR for IPX l Using snapshot routing to avoid static route configuration

20 PPP Authentication Overview Dial_Up or Circuit-Switched Network PPP Session Establishment 1 Link Establishment Phase 2 Optional Authentication Phase 3 Network-Layer Protocol Phase Two PPP authentication protocols: PAP and CHAP

21 PPP Authentication Using PAP Remote Router (SantaCruz) Hostname: santacruz Password: boardwalk Central-Site Router (HQ) Username santacruz Password boardwalk 2-Way Handshake “santacruz, boardwalk” Accept/Reject Passwords sent in clear text Peer in control of attempts

22 PPP Authentication Using CHAP Remote Router (SantaCruz) Hostname: santacruz Password: boardwalk Central-Site Router (HQ) Username santacruz Password boardwalk 3-Way Handshake Challenge Accept/Reject Uses encrypted “secret” known only to authenticator and peer Authenticator in control of attempts Response

23 PPP Authentication Commands Router (config-if) # ppp authentication chap  Forces incoming calls to answer password challenges Router (config-if) # ppp authentication pap Sets password checking for incoming calls

24 PPP Authentication Commands (cont.) Router (config-if) # username name password secret-pwd  Establishes the host name and password used during incoming call verification Router (config-if) # dialer map protocol next-hop-address name hostname Defines how to reach one or more destinations when using CHAP authentication

25 PPP Authentication Example BR0 PSTN or ISDN A B RIGHT BR0 E0S0 LEFT E0 interface s 0 (OR bri 0) ip address encapsulation ppp ppp authentication chap dialer map ip name RIGHT ! hostname LEFT username RIGHT password cisco interface s 0 (OR bri 0) ip address encapsulation ppp ppp authentication chap dialer map ip name RIGHT ! hostname LEFT username RIGHT password cisco interface s 0 (OR bri 0) ip address encapsulation ppp ppp authentication chap dialer map ip name LEFT ! hostname RIGHT username LEFT password cisco interface s 0 (OR bri 0) ip address encapsulation ppp ppp authentication chap dialer map ip name LEFT ! hostname RIGHT username LEFT password cisco

26 DDR Using Rotary Group Overview ISDN Rotary Group Several physical interfaces make up a single dialer interface Use for reaching multiple destinations at the same time

27 Rotary Configuration Overview Command defining interesting traffic Command defining interesting traffic Virtual dialer Interface Rotary Group BR0 BR1 BR2 BR3 DDR call parameters DDR call parameters Directs interesting traffic to an available interface Define interesting traffic to initiate call Associate interesting traffic to dialer interface Direct call and traffic to an interface DDR interfaces

28 DDR Rotary Commands Router (config) # interface dialer number Creates a dialer interface used in rotary group configuration Router (config-if) # dialer rotary-group number Places a physical interface into a dialer rotary group Router (config-if) # encapsulation ppp Defines encapsulation type as PPP (required by rotary group DDR)

29 DDR Rotary Example ISDN BRI l BRI3 l A BRI B

30 DDR Rotary Example (cont.) isdn switch-type basic-net3 ip route ip route dialer-list 2 protocol ip permit username 2500-A password cisco username 2500-B password cisco ! interface dialer 3 id address encapsulation ppp ppp authentication chap dialer map ip name 2500-A dialer map ip name 2500-B dialer group 2 dialer load-threshold 160 dialer fast-idle 15 dialer idle-timeout 120 ! int bri 0 dialer rotary-group 3. int bri 3 dialer rotary-group 3 isdn switch-type basic-net3 ip route ip route dialer-list 2 protocol ip permit username 2500-A password cisco username 2500-B password cisco ! interface dialer 3 id address encapsulation ppp ppp authentication chap dialer map ip name 2500-A dialer map ip name 2500-B dialer group 2 dialer load-threshold 160 dialer fast-idle 15 dialer idle-timeout 120 ! int bri 0 dialer rotary-group 3. int bri 3 dialer rotary-group 3 Set up static routes Create the virtual interface PPP encapsulation required Connect to the interesting traffic definition 160/255=60% Define interesting traffic Assign physical interfaces to the rotarygroup for virtual interface 3

31 DDR Rotary Example (cont.) isdn switch-type basic-net3 ! ip route dialer-list 2 protocol ip permit hostname 2500-B username 4000 password cisco ! interface bri 0 encapsulation ppp ppp authentication chap ip address dialer-group 2 dialer load-threshold 160 dialer map ip name dialer idle-timeout 120 ! isdn switch-type basic-net3 ! ip route dialer-list 2 protocol ip permit hostname 2500-B username 4000 password cisco ! interface bri 0 encapsulation ppp ppp authentication chap ip address dialer-group 2 dialer load-threshold 160 dialer map ip name dialer idle-timeout 120 ! Set up static route Prepare for authentication on the link Connect to the interesting traffic definition Setup details for router and the dealing device Set idle time before line is disconnected at 2 minutes (120 seconds) Cisco 2500-B

32 DDR for IPX Overview SPX Keepalive Watchdog Updates SPX Keepalive NetWare Server Spoofing allows the router to respond while the DDR interface is idle

33 Spoofing Configuration Tasks 1Turn off route caching 2Enable SPX spoofing 3 Enable Watchdog spoofing 4Set SPX idle time 1Turn off route caching 2Enable SPX spoofing 3 Enable Watchdog spoofing 4Set SPX idle time

34 DDR for IPX Example Network abcd Network 20 Ipx route abcd dialer-list 1 protocol ip deny dialer-list 1 protocol ipx permit ! interface serial 0 ipx network 10 dialer in-band dialer-group-1 no ipx route-cache ipx watchdog-spoof ipx spx-spoof ipx spx-idle-time 300 ! dialer map ipx abcd Ipx route abcd dialer-list 1 protocol ip deny dialer-list 1 protocol ipx permit ! interface serial 0 ipx network 10 dialer in-band dialer-group-1 no ipx route-cache ipx watchdog-spoof ipx spx-spoof ipx spx-idle-time 300 ! dialer map ipx abcd

35 Snapshot Routing Overview RIP/IGRP ISDN RIP and SAP Allows dynamic distance vector routing protocols to run over DDR Reduces overhead of routing updates

36 Snapshot Routing Operation Active PeriodQuiet Period Active Period Exchange routing updates Exchange routing updates Freeze routing table Time (minutes)

37 Snapshot Client/Server Operation Quite time expires Dial server router Server Router Routing Updates Client Router Send routes Client router calls server router during Active Period Periodic routing updates sent over LAN interface

38 Step 1Specify a BRI interface Step 2Configure the client router Step 3Define a dialer map Step 1Specify a BRI interface Step 2Configure the client router Step 3Define a dialer map Snapshot Configuration Tasks Server Router Client Router ISDN Step 1Specify a ISDN interface Step 2Configure the server router Step 1Specify a ISDN interface Step 2Configure the server router

39 Snapshot Routing Commands Router (config-if) # snapshot client active-time quite-time [ suppress-statechange- updates ] [ dialer ]  Configure client router Router (config-if) # snapshot server active-time [ dialer ] Configure server router Router (config-if) # dialer map snapshot sequence-number [ name name ] dial-string Define a dialer map on client router

40 Snapshot Routing Example Server Router Client Router ISDN interface BRI 0 snapshot client dialer dialer map snapshot 60 name server-router interface BRI 0 snapshot client dialer dialer map snapshot 60 name server-router interface BRI 0 snapshot server 5 dialer interface BRI 0 snapshot server 5 dialer Name “server-router” Active periods must be the same

41 Verifying Snapshot Configuration client-router # show snapshot BRI0 is up, line protocol is up Snapshot client line state up Length of active period:5 minutes Length of quite period:720 minutes Length of retry period:8 minutes Current state: quite, remaining: 390 minutes client-router # show snapshot BRI0 is up, line protocol is up Snapshot client line state up Length of active period:5 minutes Length of quite period:720 minutes Length of retry period:8 minutes Current state: quite, remaining: 390 minutes client-router # clear snapshot quite-time bri 0 client-router # show snapshot BRI0 is up, line protocol is upSnapshot client line state up Length of active period:5 minutes Length of quite period:720 minutes Length of retry period:8 minutes client-router # clear snapshot quite-time bri 0 client-router # show snapshot BRI0 is up, line protocol is upSnapshot client line state up Length of active period:5 minutes Length of quite period:720 minutes Length of retry period:8 minutes Current state: active, remaining/exchange time 4/2 minutes Updates received this cycle: appletalk

42 Dial Backup Configuration

43 Dial Backup Overview Primary Auto-dial modem Secondary Raises DTR A secondary line is available because of primary line loss or high usage

44 Dial Backup Commands Router (config-if) # backup interface interface-name Router (config-if) # backup load { enable-threshold | never } { disable-load | never } Specifies load limits for backup use Router (config-if) # backup delay { enable-delay | never } { disable-delay | never } Sets response timers for line up/down Selects a backup line

45 Dial Backup Example int s 0 backup interface serial 1 backup delay 40 never int s 0 backup interface serial 1 backup delay 40 never Backup load 60 5 Primary Secondary Auto-answer modem Auto-dial modem S0 S1 S0 S1

46 Summary Cisco routers support many bandwidth-on-demand features including: Dial-on-demand routing (DDR) DDR with access lists Rotary group DDR DDR for IPX Snapshot routing Dial backup