Piggybacking Guide
⭕🔱🇰🇦🇱🇮™🔱⭕Piggybacking, in a wireless communications context, is the unauthorized access of a wireless LAN. The usual purpose of piggybacking is simply to gain free network access rather than any malicious intent, but it can slow down data transfer for legitimate users of the network.
How piggybacking is done?
Here we will explain the concept with an example.
- There are two computers, named A and B over an IP network. They are communicating with each other using a reliable SCTP protocol.
- A sends a packet to B and waits for the response (ACK), before sending the next packet.
- Node B does the same to communicate in another direction.
- If there is no piggybacking supported, then the response of a sent packet will contain an SCTP-ACK chunk only.
- In piggybacking, if A sends the packet to B. B waits (for a small time) for a user DATA packet before sending the ACK. Once the user packet is received within a time frame, B sends both ( ACK and user DATA) in a single network message.
- On A, the message is processed as two separate chunks, one is ACK and the other is the user DATA.
- This saves the bandwidth of the network but adds a little delay.
What are the Advantages and disadvantages of piggybacking?
Advantages of piggybacking :
- The major advantage of piggybacking is the better use of available channel bandwidth. This happens because an acknowledgment frame needs not to be sent separately.
- Usage cost reduction
- Improves latency of data transfer
Disadvantages of piggybacking :
- The disadvantage of piggybacking is the additional complexity.
- If the data link layer waits long before transmitting the acknowledgment (block the ACK for some time), the frame will rebroadcast.