Introduction to Mobile IP
Mobile IP is a sweet thing and you would be amazed about its significance and benefits when you are going to know about it. So let’s begin our friendship with “Mobile IP”. Mobile + IP, these two words together are a boon to mobile networking today without which we can’t even imagine the use of cell phones and data transfer in them. Let’s know-how:
Mobile, in simple terms, as you all know means being able to move freely or being portable. For example, a “mobile bed” means a bed that can be folded and taken along freely i.e. a movable bed. The bed remains the same without changing its shape or size while you take it anywhere. You keep the bed in your bag & you travel. Similarly, “Mobile IP” has its meaning in itself – an IP that can be taken along i.e. a movable or portable IP which IP remains the same wherever you roam around irrespective of your location keeping all the other things intact such has your connection details, your identification details, etc.
As your portable bed resides in your bag, your IP resides in your cell phone or any of your digital gadgets that are connected to a network like the Internet or Intranet. The unchanging constant IP is the core meaning of Mobile IP, the IP being so faithful that even while you travel around networks or you change networks it remains as it is. Ok, now let’s begin with some questionnaire and you are definitely going to love your unnoticed long-time pal, Mobile IP because of its huge help which it has been giving you for long.
- Does your movie stop buffering while you are traveling and your location changes from one city to another?
- Did you ever notice that it’s not just you who is traveling but your mobile to travels along with you but it never says “Oops? My connection is lost & I am out of network L !!! “
- Does your call disconnect when you are talking to your buddies or your siblings while you are on a train or bus.
The answer to question no. 1 & 3 definitely for 99% of the time is definitely a huge NO. Thanks to. Mobile IP, our connection savior. This is the benefit of Mobile IP that it helps you STAY CONNECTED to the network, always. Let us learn a bit more about our fantastic buddy who helps us silently without even telling us.
Components of Mobile IP
Here are some important components that are included in the following mobile IP:
1. Mobile Node
Your devices like a laptop, cell phone, i-pad, etc.
2. Home Agent
It is the router to which your mobile device is connected located on your home network
3. Foreign Agent (FA)
- Router to which your mobile device is connected.
- When you are away from your home network, your device uses this agent to send/receive data to and from the HA (Home agent).
- Registers you as a foreigner in the foreign network similar to when you enter a new country, you are registered by a foreign country (as a newcomer) as well as your resident country (as a visitor to a foreign country with all details saved where you are going & why).
4. Care-of Address
- When you take your mobile device outside out of its home network (MyHN) & you enter a new network zone, then your device is assigned a CoA i.e. care-of address which tells your home network your current location and that you belong to the family “MyHN”.
- It is usually the IP of the foreign agent.
- For example, when you want to go to a foreign country you need to tell all your care-of details i.e. details of your home country and everything to the VISA office and embassy. After you reach a foreign country, they send all the details to your home country that you have arrived and your ID is, for example, ID-001, so this ID is your care-of address.
5. Correspondent Node (CN)
- It is the node to which your device is corresponding (a web server).
- It communicates with your device
Working of Mobile IP
It comprises of 3 phases which are explained below in detail:
1. Agent Discovery
- Whenever you enter a network, your device needs to know in which network it is, home network or foreign network?
- For this, the home agent (HA) & foreign agent (FA) advertise their services so that your device can see those advertisements and discover that it is in which network zone.
- Your mobile node i.e. your device determines its current point of attachment, if it fails to do so, it itself attempts to send messages to the agents (HA / FA) to send their advertisements.
- This happens when your device enters a foreign network.
- Your device registers itself by sending its care-of address to its home router/agent via the foreign agent or directly via collocated care-of address (CCoA) which is a temporary IP address assigned to it.
- The response is then sent by the home router to your device via FA or directly to CCoA so that the data packets can be delivered to and fro.
- The request is authenticated and has a registration time expiry before which the device has to register its current location.
- Great! You are added to their visitor lists.
- After your registration is successful & authenticated, the foreign and home agents add your device to their visitor lists.
- Tunnel is a secure path from HA to FA that ensures the successful delivery of packets to your device.
- Your device sends packets using its home IP address but shows that it is always on its home network.
- The drop of packets is solved by reverse tunneling by having the Foreign Agent send packets back to the Home Agent when it receives them from the device.
- Stay connected & online always (99% efficiency)
- It makes you seamlessly connected to a network always wherever you are whenever you are.
- No geographical barriers.
- No modification to the home IP address of your device
- Feel safe always; your mobile node can be tracked without change of IP address.
- Auto-switch & register to a new network zone. You must have noticed that your mobile network automatically “Welcomes” you when you enter a new city, that’s the power of Mobile IP.
This is a guide to Mobile IP. Here we have discussed the basic concept and components of mobile IP along with working and its benefits. You can also go through our other suggested articles to learn more –