| OID | Name | Description |
|---|
| 0.0.1 |
a |
Series A of ITU-T Recommendations "Organization of the work of the ITU-T" |
| 0.0.2 |
b |
Series B of ITU-T Recommendations - Means of expression: definitions, symbols, classification |
| 0.0.3 |
c |
Series C of ITU-T Recommendations - General telecommunication statistics |
| 0.0.4 |
d |
Series D of ITU-T Recommendations "General tariff principles" |
| 0.0.5 |
e |
Series E of ITU-T Recommendations "Overall network operation, telephone service, service operation and human factors" |
| 0.0.6 |
f |
Series F of ITU-T Recommendations "Non-telephone telecommunication services" |
| 0.0.7 |
g |
Series G of ITU-T Recommendations "Transmission systems and media, digital systems and networks" |
| 0.0.8 |
h |
Series H of ITU-T Recommendations "Audiovisual and multimedia systems" |
| 0.0.9 |
i |
Series I of ITU-T Recommendations "Integrated Services Digital Network (ISDN)" |
| 0.0.10 |
j |
Series J of ITU-T Recommendations "Cable networks and transmission of television, sound programme and other multimedia signals" |
| 0.0.11 |
k |
Series K of ITU-T Recommendations "Protection against interference" |
| 0.0.12 |
l |
Series L of ITU-T Recommendations "Environment and Information and Communication Technologies (ICTs), climate change, e-waste, … |
| 0.0.13 |
m |
Series M of ITU-T Recommendations "Telecommunication management, including Telecommunication Management Network (TMN) and netwo… |
| 0.0.14 |
n |
Series N of ITU-T Recommendations "Maintenance: international sound programme and television transmission circuits" |
| 0.0.15 |
o |
Series O of ITU-T Recommendations "Specifications of measuring equipment" |
| 0.0.16 |
p |
Series P of ITU-T Recommendations "Telephone transmission quality, telephone installations, local line networks |
| 0.0.17 |
q |
Series Q of ITU-T Recommendations "Switching and signalling" |
| 0.0.18 |
r |
Series R of ITU-T Recommendations "Telegraph transmission" |
| 0.0.19 |
s |
Series S of ITU-T Recommendations "Telegraph services terminal equipment" |
| 0.0.20 |
t |
Series T of ITU-T Recommendations "Terminals for telematic services" |
| 0.0.21 |
u |
Series U of ITU-T Recommendations "Telegraph switching" |
| 0.0.22 |
v |
Series V of ITU-T Recommendations "Data communication over the telephone network" |
| 0.0.24 |
x |
Series X of ITU-T Recommendations "Data networks, open system communications and security" |
| 0.0.25 |
y |
Series Y of ITU-T Recommendations "Global information infrastructure, Internet protocol aspects, next-generation networks, Inte… |
| 0.0.26 |
z |
Series Z of ITU-T Recommendations "Languages and general software aspects for telecommunication systems" |