Bit stuffing is the insertion of non information bits into the data bits.In high level data link control protocol(HDLC),it provides a means of synchronization.
High level Data link Control
In byte stuffing (or character stuffing), a special byte is added to the data section of the frame when there is a character with the same pattern as the flag. The data section is stuffed with an extra byte. This byte is usually called the escape character (ESC), which has a predefined bit pattern. Whenever the receiver encounters the ESC character, it removes it from the data section and treats the next character as data, not a delimiting flag.
In character stuffing tags are used to generate frames.These are the headers using which frames are generated.In this limit of information is moreCharacter Stuffing== Delimit with DLE STX or DLE ETX character flags ==== Insert 'DLE' before accidental 'DLE' in data ==== Remove stuffed character at destination ==
A program in c language to implement framing methods like character stuffing can be grave sizeCRC-32 and the variable c50.
Bit.
in bit stuffing we use data in bits !! in byte stuffing we use char !! thus in byte stuffing first char and converted in binary form and then bit stuffing is applied on it
Bit stuffing is one coding technique for preventing patterns from occurring in data. The code rate for bit stuffing is always less than the Shannon capacity.
3 bit stuffing is required
HDLC
HDLC
Bit stuffing is used for various purposes, such as for bringing bit streams that do not necessarily have the same or rationally related bit rates up to a common rate, or to fill buffers or frames. The location of the stuffing bits is communicated to the receiving end of the data link, where these extra bits are removed to return the bit streams to their original bit rates or form. Bit stuffing may be used to synchronize several channels before multiplexing or to rate-match two single channels to each other.
multiprotocol support
Differences between HDLC and PPP are(1) HDLC is cisco proprietary while PPP is an open standard.(2) HDLC does not provide authentication while PPP provides authentication like PAP and CHAP.(3) HDLC does not support compression while PPP support compression.(4) HDLC supports synchronous networks only while PPP supports both synchronous and asynchronous networks.
Bit stuffing and destuffing Zero-bit insertion and removal
Change, loss or addition of singlebits can be caused by sync. problems.
High-Level Data Link Control(HDLC) is a bit-oriented code-transparent synchronous data link layerprotocol developed by the International Organization for Standardization (ISO). The original ISO standards for HDLC are:ISO 3309 - Frame StructureISO 4335 - Elements of ProcedureISO 6159 - Unbalanced Classes of ProcedureISO 6256 - Balanced Classes of ProcedureThe current standard for HDLC is ISO 13239, which replaces all of those standards.HDLC provides both connection-oriented and connectionless service.HDLC can be used for point to multipoint connections, but is now used almost exclusively to connect one device to another, using what is known as Asynchronous Balanced Mode(ABM).
HDLC