Bao cao thuc tap ospf
- 1. ?? t¨¤i : Nghi¨ºn c?u c? ch? routing c?a cisco, m? ph?ng tr¨ºn n?n gns3 Gi¨¢o vi¨ºn h??ng d?n : Th?y V? ?? Th?ng Sinh vi¨ºn th?c hi?n : Tr?n Quang Chi?n
- 2. B¨¢o C¨¢o Th?c T?p M?c l?c I. T?ng quan v? OSPF ....................................................... 2 1. Gi?i thi?u ..................................................................... 2 2. C? ch? ho?t ??ng OSPF ............................................... 3 3. C?u h¨¬nh ??nh tuy?n OSPF ........................................... 3 a. C?u l?nh c?u h¨¬nh OSPF ............................................ 3 b. M?t s? c?u l?nh c?u h¨¬nh n?ng cao ............................. 4 II. M? ph?ng c? ch? ??nh tuy?n OSPF tr¨ºn GNS3 ............. 5 1
- 3. B¨¢o C¨¢o Th?c T?p 2 I. T?ng quan v? OSPF 1. Gi?i thi?u OSPF (Open Shortest Path First) l¨¤ giao th?c ??nh tuy?n theo tr?ng th¨¢i ???ng li¨ºn k?t ???c tri?n khai d?a tr¨ºn c¨¢c chu?n m?. So v?i RIP, OSPF l¨¤ giao th?c ??nh tuy?n n?i v¨¬ IGP t?t h?n: RIP ch? gi?i h?n trong 15 hop, h?i t? ch?m v¨¤ ??i khi ch?n ???ng c¨® t?c ?? ch?m (do thu?t to¨¢n t¨¬m ???ng ?i c?a RIP kh?ng t¨ªnh to¨¢n d?a tr¨ºn b?ng th?ng c?a ???ng truy?n nh? OSPF). OSPF ?? kh?c ph?c ???c ?i?m n¨¤y c?a RIP, n¨® c¨® kh? n?ng m? r?ng, ph¨´ h?p v?i c¨¢c h? th?ng m?ng ph?c t?p c¨® t?c ?? v?i kh? n?ng h?i t? nhanh. Trong m?ng OSPF, ng??i ta ph?n th¨¤nh nhi?u v¨´ng. C¨¢c v¨´ng n¨¤y ???c k?t n?i v¨¤o c¨´ng v¨´ng ph?n ph?i l¨¤ v¨´ng 0 (v¨´ng x??ng s?ng). Vi?c n¨¤y gi¨²p cho ng??i qu?n tr? d? d¨¤ng ki?m so¨¢t h? th?ng m?ng, c?p nh?t b?ng ??nh tuy?n. C¨¢c ??c ?i?m ch¨ªnh c?a OSPF: ? L¨¤ giao th?c ??nh tuy?n theo tr?ng th¨¢i ???ng li¨ºn k?t. ? ???c ??nh ngh?a trong RFC 2328. ? S? d?ng thu?t to¨¢n t¨¬m ???ng SPF. ? Ch? c?p nh?t khi c?u tr¨²c m?ng c¨® s? thay ??i.
- 4. B¨¢o C¨¢o Th?c T?p 2. C? ch? ho?t ??ng OSPF M?i router OSPF s? thu th?p v¨¤ qu?ng b¨¢ c¨¢c ???ng li¨ºn k?t m¨¤ n¨® nh?n ???c t? c¨¢c router h¨¤ng x¨®m ??n v¨´ng ho?c ?a v¨´ng. Sau ?¨® m?i router s? s? d?ng thu?t to¨¢n SPF ?? t¨ªnh to¨¢n c¨¢c ¡°cost¡± (chi ph¨ª ???ng ?i) v¨¤ l?a ch?n ???ng ?i t?t nh?t ??n m?ng ?¨ªch b?ng c¨¢c ???ng c¨® cost nh? nh?t. Trong m?t m?ng, c¨¢c router OSPF s? b?u ch?n m?t router ??i di?n DR (Designated Router) v¨¤ 1 router d? ph¨°ng BDR (Backup Designal Router) ?? : ? L¨¤m ?i?m t?p trung th?ng tin ??nh tuy?n. ? Tr¨¢nh hi?n t??ng loop, b?o broacast trong m?ng. 3. C?u h¨¬nh ??nh tuy?n OSPF OSPF s? d?ng kh¨¢i ni?m v¨´ng khi x?y d?ng b?ng ??nh tuy?n, m?i router ??u c¨® m?t c? s? d? li?u ??u ?? v? c¨¢c tr?ng th¨¢i ???ng li¨ºn k?t trong m?t v¨´ng. ??a ch? v¨´ng trong m?ng OSPF ???c ?¨¢nh s? t? 0 ??n 65535. N?u OSPF ??n v¨´ng th¨¬ ?¨® l¨¤ v¨´ng 0. Trong m?ng OSPF ?a v¨´ng, t?t c? c¨¢c v¨´ng ??u ph?i k?t n?i v¨¤o v¨´ng 0 (v¨´ng x??ng s?ng). Khai b¨¢o ??a ch? ???ng m?ng trong OSPF s? s? d?ng wildcard-mask ch? kh?ng ph?i l¨¤ subnet-mask. Wildcard-mask s? x¨¢c ??nh chu?i ??a ch? host n?m trong m?ng m¨¤ ta c?n khai b¨¢o. ? C¨¢ch t¨ªnh wildcard-mask - ?? t¨ªnh wildcard-mask ta l?y 255 tr? ?i l?n l??t c¨¢c octec trong subnet-mask. V¨ª d? : cho ??a ch? ???ng m?ng c¨® subnet-mask l¨¤ 255.255.255.0 ? Wildcast-mask l¨¤ : ( 255-255).(255-255).(255-255).(255-0) hay 0.0.0.255 3 a. C?u l?nh c?u h¨¬nh OSPF Router(config)#router ospf process-id Router(config-router)#network network-address wildcard-mask area area-id - Trong ?¨® :
- 5. B¨¢o C¨¢o Th?c T?p + process-id : ch? s? x¨¢c ??nh ti?n tr¨¬nh ??nh tuy?n tr¨ºn router OSPF ( ph?i gi?ng nhau gi?a c¨¢c router trong 1 m?ng ) + network-address : ??a ch? c?a ???ng m?ng k?t n?i tr?c ti?p v?i router 4 ?ang c?u h¨¬nh + wildcard-mask : x¨¢c ??nh chu?i ??a ch? host n?m trong m?ng khai b¨¢o. + area-id : x¨¢c ??nh quy ??c v¨´ng c?a router trong m?ng b. M?t s? c?u l?nh c?u h¨¬nh n?ng cao ? C?u h¨¬nh ??a ch? loopback Router (config)#interface loopback-number Router (config-if)#ip address ip-address subnet-mask ?? ??m b?o cho OSPF ho?t ??ng ?n ??nh ch¨²ng ta c?n ph?i c¨® m?t c?ng lu?n lu?n t?n t?i cho ti?n tr¨¬nh OSPF. Ch¨ªnh v¨¬ v?y c?n c?u h¨¬nh m?t c?ng loopback l¨¤ m?t c?ng lu?n l? ch? kh?ng ph?i c?ng v?t l?. N?u c¨® m?t c?ng loopback ???c c?u h¨¬nh th¨¬ OSPF s? s? d?ng ??a ch? c?a c?ng loopback l¨¤m router ID m¨¤ kh?ng quan t?m ??n gi¨¢ tr? c?a ??a ch? n¨¤y. ? Thay ??i gi¨¢ tr? ?u ti¨ºn OSPF tr¨ºn interface Router(config-if)#ip ospf priority number ? Ch?n c?p nh?t th?ng tin ??nh tuy?n t? c¨¢c interface Router(config-router)#passive interface-number ? Qu?ng b¨¢ ???ng Default statis route Router(config)# ip route 0.0.0.0 0.0.0.0 [interface|next-hop address) Router(config-router)#default-information originate
- 6. B¨¢o C¨¢o Th?c T?p II. M? ph?ng c? ch? ??nh tuy?n OSPF tr¨ºn GNS3 5