[explain] what is LLP ???

please explain waht is lower layer protocol??

Computer protocols work in layers: wires carry bits of information, and bits of information carry text, pictures, and so on. The raw bits of information are a lower level protocol that carries the text and pictures in a higher level protocol. Language works like this too: at the lowest level, paper has letters written on it. Letters are a lower-level protocol that carries words in a higher level protocol. You can think of the distinction between substantive and procedural law in the same way: the procedural layer is a lower layer that "carries" the substantive law by specifying how it is to be enforced.

Was it Link Layer Protocol you meant or just the lower layers of the OSI model? if so then what ckshivaram has said is correct. The link layer is typically the bottom 2 layers of the OSI model, Data Link and Physical. It is the layers below the IP level of the network. These two layers are used to route to physical machine addresses and to do the actual electrical transmission.
Data_Link_Layer
Physical_Layer

Or were you meaning the Logical Link Control Protocol? It is a part of the Data Link layer.
Logical_Link_Control

kimnzl said:

Was it Link Layer Protocol you meant or just the lower layers of the OSI model?

Click to expand...

i meant lower layer protocol of transmitting of information.

Lower layer protocol(s) provides framing and may provide other functions, like checksums to detect transmission errors.
Lower layer protocol(s) sound a bit generic. Is there a specific one you are after? I have not heard of a specific protocol called "lower layer protocol".
An example is that PPP is encapsulated in a Lower-layer protocol. I would suggest looking at Protocol_data_units, specifically frames and bits.

Protocol data unit - Wikipedia, the free encyclopedia

Lower layer protocol - Wikipedia, the free encyclopedia
Frame (networking) - Wikipedia, the free encyclopedia

hi kimnzl
thanks for your reply.

kimnzl said:

Lower layer protocol(s) sound a bit generic. Is there a specific one you are after? I have not heard of a specific protocol called "lower layer protocol".

Click to expand...

you are right, it is a generic term. i have read LLP in this document. i am new in this field and i am facing difficulty in understanding the terms.

LLP is referring to a collective way to transmit messages using the lower levels of the OSI model. They look to be referring to the bottom 2(2-3) layers.
This looks like a document describing their implementation of a Protocol for the transfer of messages between systems. I expect that it describes the physical (signaling) and the frame (packet) contents. This would allow creating other devices/systems that can communicate with devices/systems implementing the specification. This spec has two specs for different data types, Serial and TCPIP.

An example of a similar specification is Ethernet. "Ethernet defines a number of wiring and signaling standards for the Physical Layer of the OSI networking model as well as a common addressing format and Media Access Control at the Data Link Layer."
Ethernet - Wikipedia, the free encyclopedia