What is a MD5 Checksum?
The MD5 message-digest algorithm is a widely used cryptographic hash function producing a 128-bit (16-byte) hash value, typically expressed in text format as a 32 digit hexadecimal number. MD5 has been utilized in a wide variety of cryptographic applications, and is also commonly used to verify data integrity.
It is used on our site to ensure that a file download completed successfully. While the algorithm is not infallible, it should also provide a reasonable amount of assurance that the file downloaded from our site arrived completely and unaltered.
To use the checksum utility on OpenVMS:
$ checksum/algorithm=md5 [downloaded filename]
$ show sym checksum$checksum
CHECKSUM$CHECKSUM = "d41d8cd98f00b204e9800998ecf8427e"
The value stored in the checksum$checksum symbol should match the value on the download page. If it does not, there was a problem transferring the data to your computer and you should try to download the file again.
Note: The checksum$checksum symbol may contain either uppercase letters or lowercase letters. Since the data is a hexidecimal number, the case of the letters is not important; i.e. an uppercase "A" is equivilant to a lowercase "a".