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4.12 Which of the following statements about the spanning tree maintenance are correct ? 下列哪些關於擴張樹維護的敘述是正確的 ? |
| The root bridge will send a “Hello” BPDU periodically to each of its ports. 根橋接器會定期發送“Hello” BPDU到他所有的埠. | |
| The “Hello” BPDUs are delivered into each of the LANs along the paths of the spanning tree. “Hello” BPDUs 將會沿著擴張樹的路徑傳遞到所有的區域網路中. | |
| To have better reliability, each bridge will also forward the “Hello” BDPUs into each of its ports. 為了要有更好的可靠度，每一個橋接器也都會轉送“Hello” BDPUs 到他所有的埠. | |
| For the “root bridge”, all it’s ports are “designated ports” 根橋接器的每一個埠都是一個代理埠. |
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4.13 To construct the spanning tree of a BLAN, initially, each bridge assume itself is the “root bridge”, set each of it’s ports as a “designated” port, and send a BPDU to each port with its bridge ID, root bridge ID (itself), and the root path cost of 0. Which of the following statements are correct when a bridge (with root bridge ID = w, rpc = p) receives a BPDU (with root bridge ID = m, rpc =q) from port x (with a transmission cost of c) ? 為了建置一個橋接網路的擴張樹, 首先，每個橋接器都會將自己視為根橋接器，並將每個埠都設為代理埠，也會傳送 BPDU 到每個埠，此BPDU會包含其自己的橋接器識別碼，根橋接器辨識碼(自己的)，以及根路徑成本為0的資訊。當一個橋接器 (假設其根橋接器辨識碼為w,根路徑費用為p)，由埠x (假設其傳輸費用為c) 收到一個BPDU (其根橋接器辨識碼為m,根路徑費用為q) 時,下列哪些敘述是正確的 ? |
| port x will be selected as a new R port if w > m 埠x將會被選為新的R port 如果 w > m | |
| port x will be selected as a new R port if w = m and p > q+c 埠x將會被選為新的R port 如果 w = m 而且 p > q+c | |
| port x will be selected as a new R port if p > q 埠x 將會被選為新的R port如果p > q | |
| port x will be selected as a new R port if w < m 埠x將會被選為新的R port 如果w < m |
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4.14 Consider the procedure to construct the spanning tree. When a bridge (with root bridge ID = w, rpc = p) receives a BPDU (with root bridge ID = m, rpc =q) from port x (with a transmission cost of c). Assume w > m. Then what will happen ? 考慮建立擴張樹的過程.當一個橋接器 (假設其根橋接器識別碼=w,根路徑費用=p) 由埠x (假設其傳輸費用為c) 收到一個BPDU(其上的根橋接器辨識碼=m, 根路徑費用=q)的時候。假設w>m,則下列何者會發生? |
| Port x will be selected as a new R port. 埠x將會被選為新的R port. | |
| port x will be selected as a new D port 埠x將會被選為新的D port. | |
| A BPDU with (with root bridge ID = m, rpc =q+c) will be forwarded to all the ports, except port x. 一個BPDU (根橋接器辨識碼=m,根路徑費用=q+c) 將會被轉送到除了埠x外所有的埠. | |
| A BPDU with (with root bridge ID = m, rpc =q) will be forwarded to all the ports, except port x. 一個BPDU (根橋接器辨識碼= m, 根路徑費用=q) 將會被轉送到除了埠x外所有的埠. | |
| A BPDU with (with root bridge ID = m, rpc =p+q) will be forwarded to all the ports, except port x. 一個BPDU (根橋接器辨識碼= m, 根路徑費用=p+q) 將會轉前送到除了埠x外所有的埠. |
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4.15 Consider the procedure to construct the spanning tree. When a bridge (with root bridge ID = w, rpc = p) receives a BPDU (with root bridge ID = m, rpc =q) from port x (with a transmission cost of c). Assume w < m. Then what will happen ? 考慮建立擴張樹的過程。當一個橋接器 (根橋接器辨識碼=w,根路徑費用= p) 由埠x (假設傳輸費用為c) 收到一個BPDU (根橋接器辨識碼=m, 根路徑費用= q)。假設w < m. 則下列何者會發生? |
| Port x will be selected as a new R port. 埠x將會被選為新的R port. | |
| The BPDU will be dropped directly. 該BPDU 將會被直接丟棄. | |
| A BPDU (with root bridge ID = w, rpc = p) will be forwarded to port x. )一個BPDU (根橋接器辨識碼 = w, 根路徑費用 = p) 將會被轉送到埠x. | |
| A BPDU (with root bridge ID = w, rpc =q+c) will be forwarded to port x. A BPDU (根橋接器辨識碼= w, 根路徑費用=q+c) 將會被轉送到埠x. |
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4.16 Consider the procedure to construct the spanning tree. When a bridge (with root bridge ID = w, rpc = p) receives a BPDU (with root bridge ID = m, rpc =q) from port x (with a transmission cost of c). Assume w = m and p > q+c. Then what will happen ? 考慮建立擴張樹的過程。當一個橋接器 (根橋接器辨識碼=w, 根路徑費用= p) 由埠x (其傳輸費用為c) 收到一個BPDU (根橋接器辨識碼= m, 根路徑費用= q) .假設w = m且 p > q+c. 則下列何者會發生? |
| Port x will be selected as a new R port. 埠x將會被選為新的R port. | |
| The BPDU will be dropped directly. 該BPDU 將會被直接丟棄. | |
| A BPDU with (with root bridge ID = m, rpc =q+c) will be forwarded to all the ports, except port x. 一個BPDU (根橋接器辨識碼=m, 根路徑費用=q+c) 將會被轉送到除了埠x外的所有埠. | |
| A BPDU (with root bridge ID = w, rpc =q+c) will be forwarded to port x. 一個BPDU (根橋接器辨識碼=w, 根路徑費用=q+c) 將會被轉送到埠x. |
