cisco ccna data center

cisco ccna data center.Long distance network Infrastructure used within the carrier to transmit data for customers24.1.2 Connection TypesWAN solutions are numerous and include: analog modem and integrated services digital network (ISDN) for dial-up connections, asynchronous transfer mode (ATM), dedicated point-to-point leased lines (private circuits), digital subscriber lines (DSL), frame relay, switched multi-megabit data services (SMDS), wireless (including cellular, laser microwave, radio and satellite), X.25, cable TV, etc. Cable TV, etc. Not all of these solutions are available in every location, and not every solution is suitable for the user's needs. Therefore, it is important that you first have a general understanding of some of these services. This chapter briefly describes some of these services, and Chapter 25 describes Frame Relay.Typically, WAN connections fall into one of the following four categories. . Leased lines. such as dedicated circuits or dedicated connections.. Circuit-switched connections such as analog modems and ISDN dial-up connections. . Packet-switched connections, such as Frame Relay and X.25O. Signal element switched connections, such as ATMoExam Essentials WANs operate primarily at the physical and data link layers. Although Ethernet is used in some WAN connections, Cisco considers Ethernet to be a LAN technology. The next few subsections briefly describe these four types of connections.Leased Line Connections A leased line connection is basically a dedicated circuit connection between two sites that is equivalent to a single cable connection between the local and remote sites. The use of leased lines is most appropriate in the following two situations.. (a) The two sites are in close proximity and it is more cost effective to use a leased line.. The traffic between the two sites is fixed and there is a need to ensure that certain applications have sufficient bandwidth.