پروتکل spanning tree بصورت tcp کار میکند یا udp و دلیلش ؟

Spanning_Tree_Protocol

بسیار ممنونم از شما البته ما رو خاستن که به تقلا بیا فتیم این سوال رو هم بخاطر اینکه root bridge در جواب tcn ack میفرسته اساتید پرسید و میگن که هر جی چیزی که ack بفرسته حتما نباید tcp باشه ، نظرتون راجبه اینکه چیه که هر چیزی که ack میفرسته حتما نباید tcp باشه ؟ ممنونم از شما

آقای jeffar حتی توی سوییچ های mls هم همینطوره ؟

سوئیچ های MLS هم فرقی نمیکنه چون کلا سوئیچینگ توی لایه دو انجام میشه و STP جزء پروتکل های سویچینگ محسوب میشه و سوئیچ های MLS در لایه سوم عمل روتینگ رو برای ما انجام میدن

همچنین توی بحث روتینگ ما Loop نداریم چون بسته حداکثر TTL که میتونه داشته باشه 255 هست که حداکثر می تونه از 255 تا روتر عبور کنه

اگر ترجمه کنید متوجه می شود که نه tcp نه udp است از پرتوکل به نام Bridge Protocol Data Units استفاده می کند که بصورت مالتی کست multicast address 01:80:C2:00:00:00 ارسال می شود بالا ترجمه کن کامل تر از این جواب نیست

Bridge Protocol Data Units<left>

A bridge sends a BPDU frame using the unique MAC address of the port itself as a source address, and a destination address of the STP multicast address 01:80:C2:00:00:00.

There are two types of BPDUs in the original STP specification[6]:63 (the Rapid Spanning Tree (RSTP) extension uses a specific RSTP BPDU):

Configuration BPDU (CBPDU), used for Spanning Tree computation

Topology Change Notification (TCN) BPDU, used to announce changes in the network topology

BPDUs are exchanged regularly (every 2 seconds by default) and enable switches to keep track of network changes and to start and stop forwarding at ports as required.

When a device is first attached to a switch port, it will not immediately start to forward data. It will instead go through a number of states while it processes BPDUs and determines the topology of the network. When a host is attached such as a computer, printer or server the port will always go into the forwarding state, albeit after a delay of about 30 seconds while it goes through the listening and learning states (see below). The time spent in the listening and learning states is determined by a value known as the forward delay (default 15 seconds and set by the root bridge). However, if instead another switch is connected, the port may remain in blocking mode if it is determined that it would cause a loop in the network. Topology Change Notification (TCN) BPDUs are used to inform other switches of port changes. TCNs are injected into the network by a non-root switch and propagated to the root. Upon receipt of the TCN, the root switch will set a Topology Change flag in its normal BPDUs. This flag is propagated to all other switches to instruct them to rapidly age out their forwarding table entries.

<left>