Generally, narrowband describes telecommunication that carries voice information in a narrow band of frequencies.

Typically, Network is a group of two or more computer systems linked together

Network Access Point is a public network exchange facility where Internet Service Providers (ISPs) can connect with one another in peering arrangements. The NAPs are a key component of the Internet backbone because the connections within them determine how traffic is routed

NIC is an expansion board you insert into a computer so the computer can be connected to a network. Network interface cards provide a dedicated, full-time connection to a network.

Network Service Provider is a company that provides Internet access to ISPs (Internet Service providers). Sometimes called backbone providers, NSPs offer direct access to the Internet backbone and the Network Access Points (NAPs).

NTP (Network Time Protocol) is an Internet standard protocol that assures accurate synchronization to the millisecond of computer clock times in a network of computers. Accurate time across a network is important for many reasons; even small fractions of a second can cause problems. For example, distributed procedures depend on coordinated times to ensure that proper sequences are followed.

Running as a continuous background client program on a computer, NTP sends periodic time requests to servers, obtaining server time stamps and using them to adjust the client's clock. For more information, please refer to this page http://www.networksorcery.com/enp/protocol/ntp.htm.

Null-modem cable is a specially designed cable that allows you to connect two computers directly to each other via their communications ports (RS-232 ports). Null modems are particularly useful with portable computers because they enable the portable computer to exchange data with a larger system.