[TELECOM] 11X and N11 Codes (was 911 not universal)

JustaLurker at att.net wrote:

>> Erie PA (General System) used to use 1171 to get the fire dept >> and rescue squad well into the early 70s at least. >>=20 >> 112 was the prefix for direct-dialed LD calls. >>=20 >> 113 was information. >>=20 >> 114 was repair. >>=20 >> 116 was the test board (not for the general public, but that was >> what you got if you dialed it) >>=20 >> 118 may have had some function, but I don't remember what it was. >>=20 >> I always wondered if these sorts of numbering assignments was a >> "GTE" thing. > The 113, 114, 116 were pretty standard in step offices of Bell > companies, GTE, and other companies going back to the 1920s at > least, I believe. Except in places so small that "O-Operator" > was used for everything. >=20 > Two you didn't mention were 110 for Long Distance and 119x for > revertive ringing on party lines, the "x" representing the party > digit you wanted to call. Similar to J, W, M and one other suffix > letter I now forget for two- and four-party lines in manual areas. > On your own one-party lines you could dial 1191 to call your own > phone.

Some places used 119-1 and hang-up for ringing two-party lines, while 118+X-1 and hang-up was used for multi-party lines.

117 was frequently used for the test-board, although it was not published for the general public. 116 might frequently have been the operator for calling to nearby manual areas in semi-rural points just outside of the urban area of the town or city. These were usually individual "ring-down" lines, not actual lines on a full switchboard exchange located in the rural area. This particular 116 board in the main office of the city, and was known in many places as the "County" Operator.
As far as I know, 112 was a GTE thing only. Two adjacent cities > in North Texas got DDD about the same time. Denison (Bell-XB) > used 1+. Sherman (GTE-SxS) used 112+.=20

But even Bell SXS areas which had originating customer DDD in the later 1950s also used 112+. It's just that GTE and other independent telco areas retained using 112+ and other 11X codes longer than Bell SXS areas did.

Many larger cities with mostly common-control offices (Panel Type, > Rotary [in some independent company offices] and Crossbar) used > x11 codes. But multi-office cities that had started out all step > found that the 11x codes could be used without difficulty in 5XB > offices and probably other types of common-control offices, too.

Yes, 11X codes were introduced for SXS areas with the 1920s, while N11 codes were introduced for Panel areas with the 1920s and those Panel-dominant areas were the ones to add #1XB with the later 1930s. And yes, Panel and Crossbar areas COULD use 11X codes if necessary. There had even been the use of a two-digit code 11+ used between New York City and northeastern New Jersey, for calling back and forth between these two areas, as a multi-message-unit or "short- haul" toll call, in the later 1940s and most of the 1950s, until the time that the use of the 201 or 212 area code (depending on which direction the call was being placed) replaced the use of 11+. And New York City and northeastern New Jersey were Panel and Crossbar.=20

Circa 1960, AT&T wanted to standardize the codes used throughout the US and Canada. It didn't happen overnight. MOST of the US and Canada had phased over from 11X codes to N11 codes during the 1970s, but there were still some 'holdout' areas using 11X codes well into the


Bell wanted the use of 112+ for customer DDD from SXS areas (both Bell and independent) to be replaced with 1+. This would make a "symmetric" dial-pattern when future 0+ dialing for operator- assisted toll-billing was eventually introduced -- i.e., an eleven-digit dial pattern (eight-digits back then for home-NPA toll calls, since back then you didn't dial your home-NPA in most cases for such home-NPA toll calls).

By replacing 112+ with 1+, it also meant that the use of the other

11X codes needed to eventually be replaced with the "Panel and Crossbar" N11 format in those SXS areas. Again, it did not happen overnight. But throughout the 1960s, most Bell SXS areas phased over from 11X to N11 and 1+. Some Bell SXS areas had 11X codes for miscellaneous functions while 1+ was used for DDD, in the 1960s, by the use of a "double-headed" trunk, which actually tied-up a trunk to the tandem in case the customer was dialing 1+NXX-etc. for toll DDD, even if the customer was really dialing a 11X local or intra-office service code! Once the second-digit was dialed, the "double-headed" trunk knew whether to keep the trunk to the tandem office, or drop it. Some places routed all 11X codes thru the tandem, such as 113 Information, 114 Repair, 116 County, 117 Test Board, but internal-use codes such as party-line ring- back had to be changed.

And when SXS offices adopted N11 codes, internal-use codes for test purposes as well as party-line ring-back also were changed to some unused NNX central-office code range. This was common in the 1970s, and even 1960s. Some SXS areas used 41XX codes for such uses, this way, the most common N11 code, 411 for Directory, could be grouped together on the same selector level. Repair might have been listed as 410 or 4102. Other test-codes not listed for the general public might have been other 410X codes.

The 110 code for the Long Distance Operator in Step-dominant locations was usually abandoned, that function being combined with the local '0' Operator.

But there were many independent areas using 112+ for DDD, 113 for Directory, 114 for Repair, and many even 110 for the Long Distance Operator well after most Bell areas had phased over to 1+ for DDD,

0 for operator assistance on both local AND toll, N11 codes, and other NXX format codes for test and revertive ringing at SXS offices.

Centel in Tallahassee FL still used 11X codes into the 1970s. Lincoln NE, Lincoln Tel & Tel, was still using 11X codes into the

1980s even though ESS had already been introduced. And most of GTE-held British Columbia in Canada was still using 11X-format codes well into the 1980s, including 112+ for DDD.

As for the N11 codes, the original standard plan for customer-use codes were based on even-digits:

211 Long Distance Operator 411 Information (Directory) 611 Repair 811 Telco Business Office

The odd-digits (311, 511, 711, 911) were either unassigned, or else for internal test functions on such Panel and Crossbar exchanges back in the 1920s-60s timeframe. Some were probably test or ring- back functions only intended for internal use, while others might have been given out to the general public where needed. But I don't think that there was ever an AT&T recommended standard for the 'odd' codes 311, 511, 711, 911, back in the 1920s-60s.

The use of 911 for Emergencies wasn't first recommended and initially introduced (supposedly in an independent Contel exchange in Alabama) until the later 1960s.

Similar to how 110 for the Long Distance Operator was phased-out in SXS towns, with the local '0' Operator taking over that function -- Panel and Crossbar cities using 211 for the Long Distance Operator began to phase that out as well (again the local '0' Operator taking over that function) throughout the 1970s.

In more recent years, the FCC in the US, and CRTC in Canada, have begun to become involved with the assignments of N11 codes.

The use of 611 for Repair is still listed as such in the GENERIC lists (although its implementation has never been universal), but in more recent years, many telcos have felt that they should abandon 611 for Repair, due to the competitive nature of the local exchange carrier industry today. The use of toll-free numbers (800, 888, etc) for reaching Repair (and the Business Office) are much more common instead. They can be dialed from ANYWHERE in the US (or Canada), regardless of which type of local carrier you are originating from. If you needed to dial Repair because your line was out, and went to your neighbor to call, what if your neighbor has a different telephone company? Should the incumbent telco require that the new telcos route 611 to the incumbent? Or should 611 route to the particular telco you are using at that moment? There could be confusion to the customer as to which telco is being dialed on, and which telco is being reached. Thus, most telcos who have used 611 for Repair, have introduce ten-digit toll-free numbers instead.

The same can apply to 811 for the Business Office. And most recently, the FCC and other bodies of the US Federal Government have ordered that 811 be a universal number for "Call-Before-You- Dig" centers. Canada has also assigned 811 for non-emergency health services. Local telco uses of 811 for the Business Offices where-ever it had been used in the US and Canada have had to be discontinued (or are still to be discontinued in a few cases), replaced by ten-digit toll-free (800, 888, 877, 866, etc) numbers.

Here is the current generic list of N11 codes as it exists today. Note that not all are necessarily implemented everywhere, even in the case of 911 not yet being universally 100% in service.

This comes from the NANPA and Canadian CNAC websites,

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211 Community Information Referral Services (provided by non-government entities, such as the United Way)

311 NON-emergency Local Government Services

411 Directory Assistance

511 Travel, Traffic, Transit, Weather, road conditions, etc. info (usually provided by local/state government, or provincial and Canadian national government agencies)

611 Telco Repair (and many telcos which did use 611 have since abandoned this code in favor of ten-digit 800/888/etc. numbers)

711 Telecom Relay Service (i.e., the TTY/Voice relay operator for calls between hearing/speaking voice customers, with such impaired customers using a TTY)

811 - in the US for "Call-Before-You-Dig" 811 - in Canada for non-emergency health services

911 Emergencies

And while the 'N' in N11 refers to codes 211 through 911, the standard shorthand of 'N' meaning 2 thru 9, while any digit

0 thru 9 would be generically listed with an 'X', even 011+ 'could' be included in the list of N11 codes as the station-sent- paid access code or prefix for dialing to International/Overseas (non-NANP) locations.

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Mike Z
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