About this deal
In theory, telephony cable can be used to support 10/100 connections (not Gigabit) over short distances. If you can find a telephony cable that is not cut and is a "home run" between the two points you need to connect, and it contains at least 4 conductors, it may be possible. RJ11 is used for connecting single phone lines and uses a 6P2C or 6P4C configuration. With only 2 of the 6 available connection points, the RJ11 plug supports limited-bandwidth applications. This includes phone lines and ADSL connections. Facilitates a high speed connection between ADSL microfilter and ADSL modem router. Moulded connectors with strain reliefs provide extra durability. RJ12 connectors are also similar to RJ11 but have a 6P6C configuration. They are used to connect a phone line with the key telephone system, small exchange-like systems used by businesses to connect to the carrier on the outside and create a network of phones and extensions on the inside. RJ12 connectors can be used in place of RJ11 because RJ12 has all the connectors RJ11 needs (plus 4 extra). The answer is possibly... but without knowing more about the cable and the layout it is difficult to tell.
RJ22, also called an RJ10, is the smallest of the modular plugs. It has a 4P4C configuration and is used in handset cords. It is not an official ACTA (Administrative Council for Terminal Attachments) specification.For 10/100 Ethernet to work, you need to have a straight through connection of pins 1, 2, 3, and 6, and the other pins are not relevant/not used in this scenario. In the 568B color code, we need W/O-O/W (Pins 1&2) and W/G-G/W pairs (Pins 3&6) Pins 4, 5, 7, and 8 can be ignored (they are for PoE and Gigabit applications, which we are not going attempt with this type of cable). RJ45 connectors can support 10Gbps over Ethernet, provided the other equipment like network cables also support that speed.