What does “DB” mean, in DB-9 serial port?

1900 pts.
Tags:
Cabling
Hardware
Hubs
Network protocols
Networking
Routers
Switches
Posted on behalf of Ben: What does "DB" mean, in DB-9 serial port?

Answer Wiki

Thanks. We'll let you know when a new response is added.

“D-sub” which refers to the size. It is associated with EIA-232 spec (electronic industries alliance).

See:

More technical:

Discuss This Question: 12  Replies

 
There was an error processing your information. Please try again later.
Thanks. We'll let you know when a new response is added.
Send me notifications when members answer or reply to this question.

REGISTER or login:

Forgot Password?
By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy
  • Bobkberg
    My guess is that it stands for "D-shell Body". The "D" definitely stands for "D-shell" since that is roughly descriptive of the shape of all members of that "family" in which the description is based on the physical characteristics of the connectors, but not any of the logical ones. The "B" for "Body" is pure speculation on my part, but is based on the industrial design term "Connector Body" for connectors in general. Hope that helps, Bob
    1,070 pointsBadges:
    report
  • DrillO
    It simply means Data Bus followed by the number of pins....at least according to the A+ Study Guide
    15 pointsBadges:
    report
  • Paul144hart
    Its used wrong, but everyone does it. The letters are just manufacturer codes. I clipped a good explaination out of a wiki page (http://en.wikipedia.org/wiki/D-subminiature) D-subminiature connectors were invented by Cannon, part of ITT. Cannon's part-numbering system uses a D as the prefix for the whole series, followed by a letter denoting the shell size (A=15 pin, B=25 pin, C=37 pin, D=50 pin, E=9 pin), followed by the actual number of pins, followed by the gender (M=male, F=female). For example, DB25M denotes a D-sub with a 25-pin shell size and 25 male contacts. Cannon also produce D-subs with high-current or co-axial inserts that replace several of the normal, smaller pins. The DB13W3 variant was commonly used for high-performance video connections; this variant provided 10 regular (#20) pins plus three coaxial contacts for the red, green, and blue video signals. In the photograph above, the connector on the left is a 9-way plug (DE9M), and the one on the right is a 25-way socket (DB25F). The hexagonal pillars at either end of each connector have a threaded stud (not visible) that passes through flanges on the connector, fastening it to the metal panel. They also have a threaded hole that receives the jack screws on the cable shell, to hold the plug and socket together. Possibly because the original PC used DB-25 connectors for the serial and parallel ports, it seems that many people, not knowing the significance of the letter "B" as the shell size, began to call all D-sub connectors "DB" connectors instead of specifiying "DA," "DC" or "DE." When the PC serial port began to use 9 pin connectors, they were often called "DB-9" instead of DE-9. It is now common to see DE-9 or DE-15 connectors sold as "DB" connectors.
    0 pointsBadges:
    report
  • ItDefPat1
    I probably wouldn't disagree with the A+ comment (I'm not an A+, but have 15 years in IT). As with all things IT, there ususally are several definitions to any one question. ("MAC" for example ;-)
    15 pointsBadges:
    report
  • Poppaman2
    ItDerPat1 - Everybody knows that "Mac" stands for "Macintosh" ;)
    0 pointsBadges:
    report
  • Boumatic
    poppaman2 If mac only stands for macintosh does that mean every network adapter has a unique "macintosh" address associated with it?
    0 pointsBadges:
    report
  • ItDefPat1
    Sorry - way off topic - MAC: (network) media access controller (security) mandatory access controls (military IT Sec) mission assurance category (*sorry, steve jobs' toy didn't make the list %-) the best,most common definition for "DB" would probably be d-sub; maybe even d-shell. Or did I just contradict myself?
    15 pointsBadges:
    report
  • HumbleNetAdmin
    Hmmmm, wouldnt MAC be "Media Access Control Address" in the case of NIC's
    0 pointsBadges:
    report
  • Poppaman2
    Boumatic - Sorry, I've been doing this for far too long... As listed below my original reply, MAC is Media Access Control... My weak attempt at humor either went way below most everyone's radar or way over most everyone's head.... Sorry...
    0 pointsBadges:
    report
  • Guardian
    poppaman and itDefPat that's a good one. And for the question that's a classic cause many in IT will be asked and actually have not thought of it. IAm A+ but "Data Bus" that's has its own suspicians. Newton
    900 pointsBadges:
    report
  • Idesign4u
    Sorry to have to disagree with "wikipedia" but the D-sub miniature connectors (e.g. DB-9 and DB-25) were NOT invented by Cannon -- they were invented by my father while at AMP, Inc. in the late 1950's. Unfortunately my father never collected any royalties for his many inventions at AMP becuase of their employment policies. However, he did receive royalties from GE (General Electric) who hired him away from AMP, Inc. in 1965 and had a number of his 'inventions' patented while there.
    0 pointsBadges:
    report
  • Stevenraybo
    DB it is D-sub . the letter after DB it the pin quantity, DB-25 (25pins).DB-9(9pins)
    25 pointsBadges:
    report

Forgot Password

No problem! Submit your e-mail address below. We'll send you an e-mail containing your password.

Your password has been sent to:

To follow this tag...

There was an error processing your information. Please try again later.

REGISTER or login:

Forgot Password?
By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Thanks! We'll email you when relevant content is added and updated.

Following