[01] Isiaka A. Alimi, Department of Electrical and Electronics Engineering, School of Engineering and Engineering Technology, Federal University of Technology, Akure, Nigeria.

The current multimedia applications and services effective functionalities require reliable network connectivity that can be achieved with the implementation of network redundancy. However, the redundancy may cause broadcast storm which results in an unstable and congested network because of the network loop. Spanning-Tree Protocol (STP) is a feasible technology for loop prevention in switched networks. It employs the IEEE 802.1D algorithm to exchange the bridge protocol data unit (BPDU) messages to detect and prevent the loops by blocking certain redundant interfaces. However, the associated bandwidths of the blocked interfaces are not being utilized in the network. Therefore, to enhance system performance, physical redundant links can be logically grouped into one in order to exploit the available bandwidth with the aid of EtherChannel. This paper presents STP concepts and its implementations in switched networks. Furthermore, how the root bridge election process can be managed in a network is demonstrated and finally, practical application of an EtherChannel for bandwidth aggregation is presented.

STP, BPDU, Protocol, EtherChannel, Bridge ID, Root Bridge

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