ications, stream video, make purchases, and access social networks. Carriers are replacing DSL with Gigabit Ethernet wherever increasing amounts of fiber cabling www.TechnicalPDF.com are available. In rural areas they are replacing DSL with fixed wireless to reach customers. IP Addressing and Symmetric Speeds for Business Customers IP addresses use a numerical format such as 193.555.46.329 that is translated into words such as ABCcompany.com. IP addresses can be either static or dynamic. Dynamic IP addressing refers to the fact that carriers don't assign permanent IP addresses to particular customers or devices such as routers. Rather, carriers assign IP addresses on the fly from a pool of addresses as they are transmitted. Dynamic IP addresses can be reused after being idle for a specified period. In this way, they don't use up as many scarce IP addresses. Residential customers that publish unique e-mail addresses, e.g. johnsmith@localcompany.com obtain their e- mail address from non-telephone companies such as Google. They specify forwarding for their e-mail messages at their telephone company that provides their broadband service. Their broadband provider forwards all e-mail from johnsmith@localcompany.com using a dynamic IP address. Static IP addressing is for the most part used by business customers who buy the rights to use the address. With static IP, customers select their own unique fixed-IP address using their domain name (such as J.smith@ABCcompany) for their e-mail address. Enterprises pay an extra fee for every static IP address that they have. www.TechnicalPDF.com CARRIER GIGABIT ETHERNET Carrier Gigabit Ethernet (GigE) is a site-to-site and Internet access high-speed service. Gigabit Ethernet uses the Ethernet protocol to reach Gigabit capacity on broadband networks. It operates over fiber-optic cabling. GigE transmits data, video, images, and packetized voice (VoIP). It is the most commonly used broadband technology for enterprises. Carrier GigE was first introduced in the late 1990s. At that time