I. Understanding of basic Concepts:
The stack is the connection between the backplanes, making several switches into a whole. A cascade is a connection to a port.
Cascades are Shared, stacks are exclusive.
Cascades are connected to other switches through one port of the switch, while stacks are connected through the back of the switch.
Although both cascades and stacks can expand the number of ports, each switch or switch after cascades is still logically a plurality of devices managed by the network, while the stacked switches or switches are logically a single device managed by the network.


Ii. Differences between cascade and stack:
Switches are cascaded through up-link ports on the panel. Up-link port is actually an rJ-45 port that is reverse-connected. Connecting the up-Link port of one switch to any RJ-45 of another switch will realize the cascade between switches. The up-Link port saves the user the trouble of making a cross cable when connecting two switches together through rJ-45 port.


Features of the cascade:
1. Rj-45 port implementation using the switch;
2. Cascade cable is standard five twisted pair cable;
3. The cascade has a long distance of up to 100 meters at 10 megabits and up to 5 meters at 100 megabits;
4. Switches from different manufacturers can be cascading to each other;


Disadvantages of cascading:
1. Since the signal is transmitted from one switch to another through port RJ-45, the encoding/decoding process leads to a long delay;
2. Must occupy two RJ-45 ports (one for each of the two switches);
3. Users will lose the performance/price ratio, which is more obvious for switches with higher port costs;
4. The number of switches allowed to cascade is relatively small, 5 for 10 MB and 2 for 100 MB;
A switch stack is a stack of several switches connected together to form a large logically single switch.


Stacked features:
1. The stack passes through the special stack port, and cannot be mixed with other RJ-45 of the switch;
2. Stacked cables shall be defined by the manufacturer;
3. Stack ports are defined by the manufacturers themselves, so products from different manufacturers cannot stack with each other unless they are exactly the same;
4. As it is a trunk connection, the signal transmission between the switches is through the trunk instead of RJ-45 port, so the response time is short;
5. In a 100-megabyte network, the number of stackable switches is significantly higher than that of cascaded switches;


Disadvantages of stacking:
1. As it is connected to the trunk, the manufacturer's requirement for stacked cables is as short as possible. Too long will affect the performance of the whole system;
2. Because it is connected to the trunk, if there is a short circuit in the stack cable, the switch may not work or be damaged; Warning: Do not connect other signals, such as those coming from switch RJ-45 port, to the stack port.


Stack method of switches:
Take a section of 8-core five types of twisted pair, cut it into a 50mm section, connect one high quality RJ-45 at each end, and follow the way of one-to-one correspondence: pin 1, pin 2, pin 2... The head of RJ-45 is connected with twisted pair in the way of pin 8 and two are made in the same way. Stacking makes all switches stack together. The two lower stack ports of the upper switch are connected with the two upper stack ports of the lower switch, left to left, right to right, and so on, to achieve the stack of switches.


Warning:
1. In the stacked switch system, all switches must be turned on to form an effective data path for transmission. Even if the switch is not in use for the time being, the power should be turned on, otherwise network communication will be cut off;
2. Stack cables should not be plugged in live, otherwise the switch may be damaged;