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مشاهدة النسخة كاملة : Q about DP and BP


fatehalmsddi
23-09-2010, 02:33
السلام عليكم و رحمة الله تعالى و بركاته

As I know, a switch with lower-cost bridge will be a designated bridge . And its interface will be DP

If you could just sample this picture and explain the states of the ports

https://dc06.arabsh.com/i/02069/ia7yzsximbue.jpg

https://arabsh.com/ia7yzsximbue.html
أيمن النعيمي
23-09-2010, 02:44
طيب وين المشكلة ؟
السويتش C1 هو الرووت بريدج وكل المنافذ الموجودة في حال DP
ياريت توضح أكثر ؟
fatehalmsddi
23-09-2010, 03:01
جزاك الله خير, Sorry for ambiguity

I presume that blocked ports should be on C2 in lieu of A1 & A2
frozenEyes
23-09-2010, 06:49
جزاك الله خير, Sorry for ambiguity

I presume that blocked ports should be on C2 in lieu of A1 & A2


Because Switch C2 Bridge ID is Better (less) than Both A1 &A2
fatehalmsddi
23-09-2010, 12:59
بسم الله و الحمد لله و الصلاة و السلام على رسول الله.

جزاك الله خير, أخي.

Bridge ID = priority + VID + System (MAC). And as I got, first thing we look at the priority

The priority of C2 is higher than the ones on A1 & A2. So, A1 & A2 are more likely to be Designated Bridges with DPs on their segments  (with C2 ) please teach me.
frozenEyes
23-09-2010, 13:35
بسم الله و الحمد لله و الصلاة و السلام على رسول الله.

جزاك الله خير, أخي.

Bridge ID = priority + VID + System (MAC). And as I got, first thing we look at the priority

The priority of C2 is higher than the ones on A1 & A2. So, A1 & A2 are more likely to be Designated Bridges with DPs on their segments (with C2 ) please teach me.

How come ?!!!!

Switch C2 priority (4098) is less than Both A1 &A2 priority 32770
fatehalmsddi
23-09-2010, 19:51
Jazak Allah Kheer. Brother, i'm confused. Please put up with me and explain the picture.
frozenEyes
23-09-2010, 23:15
Jazak Allah Kheer. Brother, i'm confused. Please put up with me and explain the picture.

شوف حضرتك مراحل DP Port election هى نفس مراحل RP Port election وهى :

lowest cost /lowest forwarding bridge's id/lowest port priority and then lowest port number in received hello

مبدئيا لازم تعرف ان DP port هو البورت الذى يقوم بارسال lowest advertised cost ويتم اختياره per segment او بمعنى اخر per link (Cable) in this topology

ففى الشكل السابق سوف نجد انه تم اختيار RP port على جميع السويتشات , وايضا لاحظ ان جميع Root bridge ports تكون جميعها DP ports

سوف ترى انه عند اختيار DP port على SwC2 نلاحظ ان cost متساوية بينه وبين SWA1 فاذا فرضنا ان جميع links هى 100 Mbps فاذن SWC2 و SWA1 لديهم نفس cost الى Root Bridge وهى 19
ننتقل الى المرحلة الثانية وهى Lowest forwarding bridge's id نجد ان Switch C2 Bridge ID is Better (less) than Both A1 &A2

وعلى ذلك فان البورتات الخاصة به تكون DP ports

وبالتوفيق ان شاء الله ،، :)
fatehalmsddi
25-09-2010, 16:28
السلام عليكم و رحمة الله. جزاك الله خير أخي.

I will review the lesson then I will get back to you