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Chapter 7: Telecommunications and Networking Security.
Page 349 - in describing the presentation layer of the OSI model,
Harris writes: "If a user uses a Corel application to save a grafic,
the presentation layer would convert the graphic into a Tagged
Information File Format (TIFF), Graphic Interchange Formate (GIF), of
Joint Photographic Experts Group (JPEG) format."

What? Since when does the presentation layer change a corel file into
a JPEG?


Chapter 7: Telecommunications and Networking Security.
Page 350 - in describing the presentation layer of the OSI model,
Harris writes: "Some protocols that work at this layer are Secure
Socket Layer (SSL), Network File System (NFS), Stuctured Query
Language (SQL), and Remote Procedure Call (RPC)."


What? I thought structured query *LANGUAGE* was a *LANGUAGE* and not a
presentation layer protocol.


Is Harris wrong? Or am I misunderstanding something?

"walterbyrd" <> wrote in message
news: m...
> Chapter 7: Telecommunications and Networking Security.
> Page 349 - in describing the presentation layer of the OSI model,
> Harris writes: "If a user uses a Corel application to save a grafic (sp?),
> the presentation layer would convert the graphic into a Tagged
> Information File Format (TIFF), Graphic Interchange Formate (sp?) (GIF),
of (or?)
> Joint Photographic Experts Group (JPEG) format."
>
> What? Since when does the presentation layer change a corel file into
> a JPEG?
>

Yes this is correct. The presentation layer deals with the format of
information so it can be understood by the application layer.

Tasks like data compression, decompression, encryption and decryption are
associated with this layer. Some Presentation layer standards are involved
in multimedia operations (as in image conversion, as jpeg is effectively
lossy compression).

>
> Chapter 7: Telecommunications and Networking Security.
> Page 350 - in describing the presentation layer of the OSI model,
> Harris writes: "Some protocols that work at this layer are Secure
> Socket Layer (SSL), Network File System (NFS), Stuctured Query
> Language (SQL), and Remote Procedure Call (RPC)."
>
>
> What? I thought structured query *LANGUAGE* was a *LANGUAGE* and not a
> presentation layer protocol.

You are correct, it's not a protocol it's a database manipulation language.

>
>
> Is Harris wrong? Or am I misunderstanding something?

I hope the typos are accidental on your part and not from the book

--

-+ Shaolin +-
Discard what is useless, absorb what is not and
add what is uniquely your own.

.: http://www.security-forums.com :.

>>Some Presentation layer standards are involved
in multimedia operations (as in image conversion, as jpeg is
effectively
lossy compression).<<

That's not the same as flatly stating that the presentation layer
converts a file from one defined format to another.


"Lord Shaolin" <abuse@127.0.0.1> wrote in message news:<>...
> "walterbyrd" <> wrote in message
> news: m...
> > Chapter 7: Telecommunications and Networking Security.
> > Page 349 - in describing the presentation layer of the OSI model,
> > Harris writes: "If a user uses a Corel application to save a grafic (sp?),
> > the presentation layer would convert the graphic into a Tagged
> > Information File Format (TIFF), Graphic Interchange Formate (sp?) (GIF),
> of (or?)
> > Joint Photographic Experts Group (JPEG) format."
> >
> > What? Since when does the presentation layer change a corel file into
> > a JPEG?
> >
>
> Yes this is correct. The presentation layer deals with the format of
> information so it can be understood by the application layer.
>
> Tasks like data compression, decompression, encryption and decryption are
> associated with this layer. Some Presentation layer standards are involved
> in multimedia operations (as in image conversion, as jpeg is effectively
> lossy compression).
>
> >
> > Chapter 7: Telecommunications and Networking Security.
> > Page 350 - in describing the presentation layer of the OSI model,
> > Harris writes: "Some protocols that work at this layer are Secure
> > Socket Layer (SSL), Network File System (NFS), Stuctured Query
> > Language (SQL), and Remote Procedure Call (RPC)."
> >
> >
> > What? I thought structured query *LANGUAGE* was a *LANGUAGE* and not a
> > presentation layer protocol.
>
> You are correct, it's not a protocol it's a database manipulation language.
>
> >
> >
> > Is Harris wrong? Or am I misunderstanding something?
>
> I hope the typos are accidental on your part and not from the book