A good and reliable network can help you in running a business operation seamlessly. That is the reason why a professionally reliable network always come with certain vital features that ensure unflinching results as per the given command. One such trusted feature is the network switch.

A network switch helps in controlling and guiding the flow of the network traffic and currently accessible in two distinctive forms, i.e. physical switches and virtual switches.

 Introduction

Here, we are going to shed some light over the physical switch vs virtual switch distinction and try to find out which can turn out to be the finest choice for your business needs among the two. First and foremost, let us have a glance over what both the varieties of switches are all about.

A physical switch is basically a tangible device that one can touch and feel, guiding the flow of the network traffic by basically forwarding the data packets to the designated device that leads to a well enabled range of networking functions in exchange. Physical Network switch is an individual entity which connects to physical devices like router, firewall, Physical switch, Server etc.

On the other hand, virtual switches function as intangible software that enable the network components, such as virtual machines to interact with each other. They are identical to the physical switches over one aspect that they function in an isolated manner without sharing the resources with one another. Virtual switches are used for connecting Virtual environments (VMs) to other VMs and also establish connections with physical networks.

Physical Switch vs Virtual Switch:

The following table would help you define the line of difference between the physical and virtual switches and reach onto to the inference of making the finest choice-

Conclusion

It is utterly true that both physical and virtual switches have their own merits and demerits. So in order to make a prudent physical switch vs virtual switch decision, it is suggestive to evaluate the system configuration and whether it is conducive merely to hardware switch terminals or could be expanded to virtual switch contours. If you are seeking better bandwidth capacity and would like to assess each data packet before passing them through the terminal then virtual switches are recommend. Rest of the aspects can function seamlessly in either case.

Related – VMware Distributed Switch vs Standard Switch

Switching is the important mechanism that provides communication between different endpoints or different computers and manages the data flow between the two end points. There are three types of switching techniques –

• Circuit switching
• Packet switching
• Message switching

In this previous post we discussed Circuit Switching. In this post we will discuss Packet Switching.

Packet switching is a switching method in which data  is transferred in the form of small broken pieces of variable lengths. These broken pieces of data are called as packets. The data is transferred in the form of packets, transmitted to the network line and  reassembled at the destination making a complete file.

Thus, Packet Switching method uses Store and Forward technique. Each hop will store the packet and then forward the packets to the next host destination.

Types of Packet Switching

There are two types of packet switching :

• Virtual Circuit Packet Switching
• Datagram Packet Switching

VC Packet Switching:

VC Packet Switching is an approach in which a logical path or virtual circuit connection is done between sender and receiver. VC stands for Virtual Circuit. Thus, a predefined route is created and all packets will follow these predefined paths. In this logical connection, all routers or switches are provided with a unique Virtual Circuit ID to uniquely identify the virtual connections. It also has the same three-phase protocol used in circuit switching – Setup Phase, Data Transfer Phase and Tear down Phase. WAN, ATM, frame relay and telephone networks use virtual circuit approach.

In this diagram, four users connected with a four-switch network are showing  data flow in Virtual circuit mode. The four switches are connected with each other and share the communications path with each other. To transfer data from USER A to the USER D, a predefined route is established, that passes from USER A to  S1 to S2 to S3 and then finally to USER D. In this predefined route  S1, S2, S3 are provided with a unique Virtual Circuit ID to identify the virtual connection, so the data is bound by the predefined path and could not choose another route.

Datagram Packet Switching:

In Datagram packet switching each packet has all the necessary information like Source address, destination address etc. So each packet is treated independently. They can choose different routes for transmitting data inside the network. There is no predefined route. So, the packets can be received in any sequence at the destination. Packets in this approach are called datagrams. Datagram approach can cause the datagrams to reach the destination out of order. Additional end system protocols need to be configured, to secure guaranteed packet receiving. This mode of packet switching, doesn’t involve setup, transfer and teardown phase.

In this diagram, again four users are connected with a switch- network , and  data is transferred from USER A  to USER D. The data contains two packets (or datagrams) – a and b. In Datagram Packet Switching, PACKET a & PACKET b choose different  paths to reach the final destination i.e. USER D.

PACKET a :

USER A – S1 – S4 – S3 – USER D

PACKET b :

USER A – S1- S5 – S3 – USER D

The different paths can be chosen depending on the delay time and congestion on other paths.

FAQs

• Is Packet Switching still in use?
• Yes, Packet switching is used in the Internet and most local area networks.  Newer mobile phone technologies (e.g., GSM, LTE) also use packet switching.
• Which switching method is most secure?

Switching is an important mechanism that provides communication between different networks or different computer(s) and manages the data flow between the two end points. There are three types of switching techniques –

• Circuit switching
• Packet switching
• Message switching.

Here we will discuss Circuit switching.

Circuit switching

It is a switching method in which a dedicated physical path is formed between two points in a network i.e. between the sending and the receiving devices. These dedicated paths are created by a set of switches connected by physical links. Circuit switching is the simplest method of data communication that has a fixed data rate and both the subscribers need to operate at this fixed rate.

Phases Of Circuit switching Communication

It has basically three phases :

Establishment or Setup Phase  –

A dedicated circuit or path is established between the sender and receiver before the actual data transfer. End-to-End addressing  i.e. source address and destination address, is required for creating a connection between two  physical devices.

Data Transfer Phase –

Data transfer only starts after the setup phase is completed and a physical, dedicated path is established. The data flow is continuous and there may be periods of silence in data transmitting. Generally all internal connections are made in duplex form. The switches use time slot (TDM) or the occupied band (FDM) to route the data from the sender to the receiver and no addressing method is involved.

TDM (Time Division Multiplexing) and FDM (Frequency Division Multiplexing) are types of multiplexing techniques that are used to transmit multiple signals over a single channel. In FDM, multiple signals are transmitted by occupying different frequency slots while in TDM, the signals get transmitted in multiple time slots.

Disconnect or Teardown Phase –

When one of the subscribers (either the sender or the receiver) needs to disconnect, a disconnect signal is sent to each switch to release the resource and break/disconnect the connection.

Example

One of the major example of Circuit Switching is the Plain Old Telephone System (POTS).

Advantages of Circuit Switching

1. The data rate is fixed and dedicated as the connection is established using dedicated physical path.
2. Once the circuit is established, there is no waiting time and the data transmission delay is negligible.
3. Since a dedicated path is established, it is a good choice for continuous transmission over a long duration.

Disadvantages of Circuit Switching 

1. Since the connection is dedicated it cannot be used for any other data transmission even if the channel is free.
2. It is inefficient in terms of utilization of the system resource. As it is allocated for the entire conversation, we can’t use the resource for other connection.
3. More bandwidth is required for the dedicated channels .
4. Establishment of physical links between senders and receivers takes huge time prior to the actual data transfer.

FAQs :

• Is circuit switching faster than packet switching?
• Packet switching is faster than Circuit switching. Packet switching is more efficient as all the bandwidth can be used at once and it doesn’t have to deal with a limited number of connections that may not be using all that bandwidth.