【正文】 Server基本設置：選用Cisco2511作為訪問服務器,。263的ISDN電話號碼為2633，用戶為263，口令為263，所涉及的命令如下表：任務 命令 指定接口通過PPP/IPCP地址協(xié)商獲得IP地址 ip address negotiated 指定內(nèi)部和外部端口 ip nat {inside | outside} 使用ppp/pap作認證 ppp authentication pap callin 指定接口屬于撥號組1 dialergroup 1 定義撥號組1允許所有IP協(xié)議 dialerlist 1 protocol ip permit 設定撥號，號碼為2633 dialer string 2633 設定登錄263的用戶名和口令 ppp pap sentusername 263 password 263 設定默認路由 ip route bri 0 設定符合訪問列表2的所有源地址被翻譯為bri 0所擁有的地址 ip nat inside source list 2 interface bri 0 overload 設定訪問列表2，允許所有協(xié)議 accesslist 2 permit any 具體配置如下：hostname Cisco2503 ! isdn switchtype basicnet3 ! ip subnetzero no ip domainlookup ip routing ! interface Ethernet 0 ip address ip nat inside no shutdown ! interface Serial 0 shutdown no description no ip address ! interface Serial 1 shutdown no description no ip address ! interface bri 0 ip address negotiated ip nat outside encapsulation ppp ppp authentication pap callin ppp multilink dialergroup 1 dialer holdqueue 10 dialer string 2633 dialer idletimeout 120 ppp pap sentusername 263 password 263 no cdp enable no ip splithorizon no shutdown ! ip classless ! ! Static Routes ! ip route bri 0 ! ! Access Control List 2 ! accesslist 2 permit any ! dialerlist 1 protocol ip permit ! ! Dynamic NAT ! ip nat inside source list 2 interface bri 0 overload snmpserver munity public ro ! line console 0 exectimeout 0 0 ! line vty 0 4 ! end 5. basicnznet3 New Zealand Net3 switches 3. 2. 它是一種數(shù)據(jù)包交換技術。 x25 map ip 110102 broadcast ! 有關命令:任務 命令 encapsulation x25 [dce] x25 address 設置遠方站點的地址映射 x25 map protocol address [protocol2 address2[...[protocol9 address9]]] x121address [option] 設置最大的雙向虛電路數(shù) x25 htc citcuitnumber1 設置一次連接可同時建立的虛電路數(shù) x25 nvc count2 設置x25在清除空閑虛電路前的等待周期 x25 idle minutes 重新啟動x25，或清一個svc，啟動一個pvc相關參數(shù) clear x25 {serial number | cmnsinterface macaddress} [vcnumber] 3 清x25虛電路 clear x25vc 顯示接口及x25相關信息 show interfaces serial show x25 interface show x25 map show x25 vc 注：虛電路號從1到4095，Cisco路由器默認為1024，國內(nèi)一般分配為16。 當鏈路為E1時, channelgroup編號為030, Timeslot范圍131. controllers e1觀察controller狀態(tài),以下為幀類型為crc4時controllers正常的狀態(tài). IP地址分類IP地址分為網(wǎng)絡地址和主機地址二個部分，A類地址前8位為網(wǎng)絡地址，后24位為主機地址，B類地址16位為網(wǎng)絡地址，后16位為主機地址，C類地址前24位為網(wǎng)絡地址，后8位為主機地址，網(wǎng)絡地址范圍如下表所示：種類 網(wǎng)絡地址范圍 A　 B C D E 2. 改變命令狀態(tài) mask is /24 在設置完所有接口的參數(shù)后，系統(tǒng)會把整個設置對話過程的結果顯示出來： The following configuration mand script was created: hostname Router enable secret 5 $1$W5Oh$p6J7tIgRMBOIKVXVG53Uh1 enable password pass ………… 請注意在enable secret后面顯示的是亂碼，而enable password后面顯示的是設置的內(nèi)容。 Configure for modems? [yes/no]: yes 4) 進入設置對話過程后，路由器首先會顯示一些提示信息： System Configuration Dialog At any point you may enter a question mark 39。 5.然后路由器會問是否進入設置對話：Would you like to enter the initial configuration dialog? [yes]: 如果按y或回車，路由器就會進入設置對話過程。 是否使用TCP頭壓縮： 設置接口的IP地址： 任務 命令 登錄遠程主機 telnet hostname|IP address 網(wǎng)絡偵測 ping hostname|IP address 路由跟蹤 trace hostname|IP address 　6. 使用網(wǎng)絡地址翻譯（NAT）NAT（Network Address Translation）起到將內(nèi)部私有地址翻譯成外部合法的全局地址的功能，它使得不具有合法IP地址的用戶可以通過NAT訪問到外部Internet.當建立內(nèi)部網(wǎng)的時候,建議使用以下地址組用于主機,這些地址是由Network Working Group(RFC 1918)保留用于私有網(wǎng)絡地址分配的.l Class B: to l 由于在Router1上端口Serial ，所以不需要在Router1上添加靜態(tài)路由。CHAP(Challenge Handshake Authentication Protocol)和PAP(Password Authentication Protocol) (PAP)通常被用于在PPP封裝的串行線路上提供安全性認證。DCE設備是專用通信設備，如調(diào)制解調(diào)器和分組交換機。 ip address Router2: interface Serial0 我們知道為了避免路由循環(huán)，路由器支持split horizon法則，它只允許路由更新被分配到路由器的其它接口，而不會再分配路由更新回到此路由被接收的接口。DLCI的值一般由幀中繼服務提供商指定。3. 所建的這兩用戶的password必須相同。 aaa accounting network startstop tacacs+ 指定Tacacs服務器地址 tacacsserver host 在Tacacs+服務器和訪問服務器設定共享的關鍵字，訪問服務器和Tacacs+服務器使用這個關鍵字去加密口令和響應信息。1. router1 00:03:50: %LINK3UPDOWN: Interface BRI0:1, changed state to up 00:03:50: BRI0:1:PPP callback Callback server starting to router2 572 00:03:50: BRI0:1: disconnecting call 00:03:50: %LINK3UPDOWN: Interface BRI0:1, changed state to down 00:03:50: BRI0:1: disconnecting call 00:03:50: BRI0:1: disconnecting call 00:03:51: %LINK3UPDOWN: Interface BRI0:2, changed state to up 00:03:52: callback to router2 already started 00:03:52: BRI0:2: disconnecting call 00:03:52: %LINK3UPDOWN: Interface BRI0:2, changed state to down 00:03:52: BRI0:2: disconnecting call 00:03:52: BRI0:2: disconnecting call 00:04:05: : Callback timer expired 00:04:05: BRI0:beginning callback to router2 572 00:04:05: BRI0: Attempting to dial 572 00:04:05: Freeing callback to router2 572 00:04:05: %LINK3UPDOWN: Interface BRI0:1, changed state to up 00:04:05: BRI0:1: No callback negotiated 00:04:05: %LINK3UPDOWN: Interface VirtualAccess1, changed state to up 00:04:05: dialer Protocol up for Vi1 00:04:06: %LINEPROTO5UPDOWN: Line protocol on Interface BRI0:1, changed state to up 00:04:06: %LINEPROTO5UPDOWN: Line protocol on Interface VirtualAccess1, chang ed state to up 00:04:11: %ISDN6CONNECT: Interface BRI0:1 is now connected to 572 router1 4. ntt Japanese NTT ISDN switches primaryntt Japanese ISDN PRI switches North America BRI的B信道速率為64Kbps,用于傳輸用戶數(shù)據(jù)。 幀中繼point to point配置實例：2. Router: interface Serial0 encapsulation x25 x25 address 110103 x25 htc 16 x25 nvc 2 ! interface pointtopoint ip address x25 map ip 110101 broadcast ! interface pointtopoint ip address x25 map ip 110102 broadcast ! router rip network network ! 四、Frame Relay 1. Router: interface Serial0 ip address x25 htc 16 設置如下：Router1: hostname router1 username router2 password xxx interface Serial0 ip address clockrate 1000000 ppp authentication chap ! Router2: hostn