IT Networking Design: Redundancy, Routers, and STP

This document presents a comprehensive solution to an IT networking design assignment, addressing critical aspects of network infrastructure and protocols. The solution begins by analyzing redundancy issues at the distribution and core layers, proposing solutions for Layer 2 and Layer 3 redundancies using protocols such as HSRP, VRRP, and ether channels. It then differentiates between routers and Layer 3 switches, highlighting their routing capabilities and limitations. The document further explores the advantages and disadvantages of using STP (Shielded Twisted Pair) cables, including resistance to interference, speed, and data security. Finally, it discusses the advantages of EtherChannel, comparing LACP and PAgP protocols and their modes of operation. The assignment solution is well-structured, providing a clear understanding of the concepts and practical applications in IT networking design.

Running head: IT NETWORKING DESIGNING
IT networking designing
Name of the student:
Name of the University:
Author Note:

1IT NETWORKING DESIGNING
Question 1: Redundancy issues at distribution and core layer. Solutions for layer 2 and
layer 3 redundancies.
In the three-layer model distribution layer is the smart layer. QoS policies, filtering
and routing are managed in this layer. An important factor in this layer is redundancy.
Thousands can be affected if the distribution layer fails. With redundant links, distribution
layer is deployed in pairs and is linked to the access layer devices. Importance should be
placed for supervisor engines and redundant power supplies ("Build Your Skills: The three-
layer hierarchical model", 2018). At the distribution layer HSRP (Hot standby routing
protocol) must be used for proving fault tolerance. In case of core layer, speed is an important
part since the task of the core layer is to perform switching between switch blocks at high
speed.
Layer 2 redundancy can be implemented through VRRP (virtual router redundancy
protocol) and also through HSRP (Hot standby routing protocol). For layer 3 redundancy,
HSRP can be used. Additionally, ether channels can be used for both.
Question 2: Difference between routers and layer 3 switches. Routing capabilities and
limitation of layer 3 switch.
It is established that layer 3 switches are much faster than routers however routers
have some advanced functionalities. Layer 3 destination address for every packet is analyzed
by a router and based on that it devises the next hop for it. Ever packet encounter delay
because of the process. In case of layer 3 switch, a cache entry is made whenever routing
table searches for destination.
For routing capability, a cache entry is made as discussed above. It contains the next
hop address and source-destination pair. Once this cache is put in place, other packets with

2IT NETWORKING DESIGNING
the same source-destination pair does not have to follow the entire process. From, the cache
next hop address is directly picked up. Limitations are limited security features, no firewall,
reduced route table size and limited routing protocol support (Router, 2018).
Question 3: Advantages and disadvantages of using STP.
STP (Shielded twisted pair) cable is used telephone networking and in computers.
One of the distinct advantage is resistance to interference. This cabling repels interference
from outside source. The second advantage is speed. It can transmit data at speed up to
100mb per second. The third advantage is data security. Data sent via coaxial and unshielded
cabling is much less secure than data transmitted via STP cable.
Disadvantages of STP cable is also there. One of the disadvantages is that STP is
much costlier than UTP (Unshielded twisted pair). The second disadvantage is that it is much
more difficult to install when compared to unshielded twisted pair ("Shielded Twisted Pair
Cables", 2018).
Question 4: Advantages of ether channel. To provide comparison between two
protocols.
Ether channels has multiple advantages. Instead of using individual ports, ether
channel interface can be used for configuration tasks. There is no need to upgrade since it
relies on existing switch ports ("5.1.1.2 Advantages of EtherChannel", 2018). In-between
links load balancing takes place which are part of same ether channel. The overall link is seen
as a logical connection since ether channels provide redundancy.
LACP is standard based negotiation protocol whereas PAgP is Cisco proprietary
negotiation protocol. Port aggregation protocol has two modes namely auto mode and

3IT NETWORKING DESIGNING
desirable mode whereas Link aggregation control protocol has active mode and passive
mode.
References:
5.1.1.2 Advantages of EtherChannel. (2018). Ies-sabadell.cat. Retrieved 1 May 2018, from
http://www.ies-sabadell.cat/cisco/cisco/cisco-switched-networks/course/
module5/5.1.1.2/5.1.1.2.html
Build Your Skills: The three-layer hierarchical model. (2018). TechRepublic. Retrieved 1
May 2018, from https://www.techrepublic.com/article/build-your-skills-the-three-
layer-hierarchical-model/
Router, A. (2018). Advantage of layer 3 switch over Router.
Networkengineering.stackexchange.com. Retrieved 1 May 2018, from
https://networkengineering.stackexchange.com/questions/25643/advantage-of-layer-
3-switch-over-router
Shielded Twisted Pair Cables. (2018). Networking-communications.knoji.com. Retrieved 1
May 2018, from https://networking-communications.knoji.com/shielded-twisted-pair-
cables/