What is this?

This is my personal archive of Bell System Practices. BSPs were published by AT&T and the various Bell System operating companies over the course of the 20th century. These documents mostly date from as far back as the early 1920s into the early 2000s. They cover every possible aspect of the Bell System from administrative activities to equipment design and maintenance to things like sweeping the floors in telephone central offices.

Is this meant to compete with or replace the TCI Library?

Not at all. I recently (late 2019) decided to finish the catalog I'd been building of BSPs since the early 2000s and decided that it would make sense to share it in a format I like. The TCI Library has much more content covering all types of things that I'm not putting here. I already had many of the BSPs from my archive available at http://etler.com/docs/BSP. This is just a more organized way of presenting it.

How are BSPs organized?

There are two major BSP organization schemes. The first, which began sometime in the early 1930s, put BSPs into broad letter categories with a numbering format like C26.522. This became unwieldy by the late 1950s so the 9-digit plant series was introduced. These are in a format like 501-100-101 where the first three digits indicates a division, the next three a layer, and the final three a topic.

Why is the format of titles not always consistent?

As opposed to the official indices that AT&T published, I've made a point of reproducing the titles of BSPs as closely as possible to what's in each document. This changed over the years due to evolving Bell System standards. I've tried to keep consistent even down to the way commas were used (as much as the lack of an Oxford comma in some places pains me). The only places where I've modified things is either for clarity or to correct obvious errors.

Do you have a copy of...?

If you're looking for a BSP section that's not linked here, it's highly unlikely that I have a copy. I've digitized the vast majority of my paper holdings at this point with the exception of some G series outside plant BSPs from the 1940s and 1950s and some handbooks. A great resource to ask about BSPs that aren't digitized yet is the TCI mailing list.

Why don't you include...?

I've limited this archive to BSPs and maybe a few other things that are similar (I'll probably add DFMPs, and BSRS documents eventually). I'm not currently planning on adding SDs, CDs, EDs, etc. or documents published by other companies that fall outside of the BSP numbering scheme. There's just too many and I don't believe I have anything unique that isn't hosted elsewhere right now.

For all these things I highly recommend the TCI Library as a fantastic resource. I also have some other things in open directory format located at http://etler.com/docs but that's very hit and miss.

Did you scan all of these?

By no means did I scan all of these, though by my estimation I've digitized about 200,000 pages of documents over the years. The documents in this archive have been contributed by a large number of people. I am highly appreciative of this effort.

I found an error, how can I report it?

Please let me know by emailing me at sametler[at]gmail[dot]com. Any feedback is greatly appreciated!

Your copy of a BSP is slightly different from the one I have saved / the one in the TCI Library / etc. Why?

As I mention above, this is my personal archive and I've done things to make my life easier such as OCR, cleaning things up, and other optimizations.

Can I contribute?

If you have copies of BSPs that are digitized that aren't in this archive please let me know. I'll happily add them! If you have paper BSPs that are in need of scanning, also let me know. The caveat is that while I am happy to scan things, I spend about half my life traveling and don't have the time that I used to to sit in front of a scanner for hours. I have some stuff I'm working on, but it will take a long time. I will give higher priority to important missing items like general descriptive BSPs for systems that haven't been digitized and the various 800 Divisions covering Equipment Design Requirements which are rare. Please e-mail me at the above address if you want to discuss what you have.

Of special note, in the late 1990s and early 2000s, some BSPs were digitized and regrettably had OCR replacement done on them. Instead of having the OCR embedded under the image, the image was replaced by text. This is a uniformly bad idea when it comes to documents full of part numbers like BSPs since OCR even today can be unreliable without detailed editing. If you happen upon one of these BSPs and have a physical copy that we can re-scan, please let me know!

If you're looking to contribute money, thank you, but I'm doing well enough to support this site right now.

Can you provide mass download links?

In the past I've provided tar.gz files for sets of BSPs. As the archive is close to 50 GB at this point, I'm not doing that any more. I highly recommend using a tool like wget for mass downloads.

Some notes on organization...

While the Plant Series BSPs were fairly well organized, with tens of thousands of sections published over the years, some issues were bound to pop up. I've organized things in a way that makes sense to me and have tried to be consistent. Some things you'll notice...

I usually keep addenda separate from the main BSP. In some cases though, when I obtained the document, revised pages were already incorporated into the BSP. Earlier in my archiving days I would keep the addendum page separate. These days I don't do that and instead keep it as the front page while appending the issue number with an R for "revised" or "reissued". So Issue 1R would indicate this is Issue 1 of the document as revised by an addendum. One of my failings with addenda early on was not accounting for duplication of addenda issue numbers over different issues of a BSP. In rare situations there might be two addenda issued decades apart with the same issue number. I'm working on making this better but it will take time.

Some BSPs were released in condensed formats. I've tried to append the letter C for "condensed" to those issue numbers. There are also some BSPs that are incomplete. These will have the letter I appended to their issue number. These are rare. To make things more confusing, some BSPs have the letter D appended by the publishers to the issue number. This stems from the Bell Labs classification letters described in 005-100-101, Sec. 2.09 and is covered in 000-010-010, Sec. 4.01.

Due to the fact that I've included pretty much everything I've come across with BSP style numbering in this archive, there are practices from a number of companies that spun out of the Bell System over the years such as Avaya. The numbering is not always consistent with the over Plant Series methods.

Some BSPs have appendices which make more sense to keep separate. These are indicated by the letter X follow by number.

In some cases, there are both handbook and full sized versions of the same section and issue. These are noted as such to avoid confusion.

Some BSPs were issued by local Operating Companies. In these cases, two letters are appended to the BSP number. Most of these can be found in 000-010-010, Sec. 11.04 though there are others that began to be used post-Divestiture. It's not so much of a problem with the Plant Series, but in the previous lettered series of BSPs, the suffixes weren't defined yet. I have added these to avoid confusion.

What software does this website run on?

This is really barebones. All of the HTML is generated by about 100 lines of perl script that I wrote, and a lot of that is the HTML headers and formatting tags. It takes input from a spreadsheet I keep locally with all of this information. It's really basic. So keep that in mind if you want to complain about the layout or lack of features! :-)