"Salai Sivamal.G" wrote:
> 
> Hi all,
> 
> I have a doubt regarding Length octets in BER.
> My question is, How to specify length octets, if it's value is greater than
> '255'.

The same way as if they are greater than 127!!!

> Because we cannot specify it in a single octet.

255 can not be encoded using a single octet either.

The rules are defined in X.690.

Shortly:
Definite length:
length < 128: single octet. (Short form)
length >= 128: multiple octets (Long form)
If first octet has MSB set to 1, it signals multiple octet encoding.
The remaining 7 bits are used to give the number of successive octets
used to encode the length.
127 is encoded as: 0x7F
128 is encoded as: 0x81 0x80
255 is encoded as: 0x81 0xFF
302 is encoded as: 0x82 0x01 0x2E

Indefinite length:
Length is encoded as: 0x80
Terminated after the constructed contents by 0x00 0x00


Please consult the freely available standards or one of the books on
ASN.1/BER, and you will gain a lot of time.

Best regards
Egon Andersen

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