TAILIEUCHUNG - Giáo Trình CIs+ part 89

Tham khảo tài liệu 'giáo trình cis+ part 89', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | no ip address bridge-group 1 bridge-group 1 output-type-list 200 int tunnel 0 tunnel source interface loopback0 tunnel destination access-list 200 permit 0x6000 0x600f Router B int e0 ip address bridge-group 1 int loop0 no ip address bridge-group 1 bridge-group 1 output-type-list 200 int tunnel0 tunnel source interface loopback0 tunnel destination access-list 200 permit 0x6000 0x600f From Question 50 Subject Why is measuring collisions meaningless endeavour A more useful calculation would be to multiply collisions by 704 and then divide that by 10000000 t to show the total overhead percentage used by collision detection. 704 is the number of bit-times consumed by a collision - 96 bittimes of interframe gap 512 bits of collision an additional 96 bittimes of interframe gap next packet is ready to transmit. First of all you shouldn t count the interframe gap twice. The collision event uses an interframe gap but the next one actually belongs to the next frame it would be there whether or not a collision occured. More important 511 bit times is the MAXIMUM time consumed by a collision in the absolute worst-case. This requires a network with maximum extent--longest possible cables maximum repeaters devices with absolute worst-case timing parameters. In most small networks . a single 10BASE-T hub nearly all collisions occur during the preamble and the time consumed by the collision is just 96 64 32 192 bit-times IFG Preamble Jam . Unless you know the precise instant in which each collision occurs you cannot calculate the bandwidth lost to collisions. By the way the maximum collision fragment is 511 bits not 512--at 512 bits it becomes a valid frame. In addition while some Ethernet controllers do return a collision count as part of the transmit status for each frame many do not provide the SNMP RMON driver with the exact number of collisions. Instead the status indicates one of OK no deferral .

Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.