Synchronous digital hierarchy architecture is an advanced technology that allows for instantaneous  rerouting and eliminates downtime in the event of a fiber cut. In addition, synchronous digital hierarchy offers  better reliability and performance for optical fiber transmissions at a lower operating cost. In December 2002,  we installed synchronous transport module 64 multiplexer and 32-wavelength dense wavelength division  multiplexing equipment on our long-haul backbone network. Our synchronous transport module 64 multiplexer  can multiplex several low speed signals into a 10 gigabits per second, or Gbps, high-speed signal. Dense  wavelength division multiplexing equipment uses a technology that puts data from different sources together  on an optical fiber with each signal carried on its own separate wavelength. Both synchronous transport module  64 multiplexer and dense wavelength division multiplexing equipment can increase our network capacity.  Furthermore, between 2003 and 2007, we deployed 32-wavelength optical add-drop multiplexer rings in Taipei,  Taichung, Tainan and Kaohsiung. Between 2007 and 2011, we will deploy 40/80-wavelength Re-configurable  Optical Add-Drop Multiplexer, or ROADM, rings for backbone transmission network in order to provide new  data services such as gigabit Ethernet, fiber channel, 2.5 gigabit and 10 gigabit packet over synchronous digital  hierarchy and 10 gigabit Ethernet. We have already completed the deployment of 397 wavelength ROADM  rings by the end of 2010. To meet the demand for broadband services, we will install an optical cross-connect,  or OXC, network and a next generation synchronous digital hierarchy network, which provides gigabit Ethernet  over synchronous digital hierarchy service, between 2009 and 2013.  Based on the transmission network described above, we have been providing connection circuit service of 10  gigabit packet over synchronous digital hierarchy and 10 gigabit Ethernet to the government’s Taiwan Advanced  Research and Education Network since November 2006 and continued the service until November 2012.  As part of our strategic focus on the internet and data markets, our local loop connections use ADSL  technology. This enables us to deliver high-speed internet, multimedia and other data services to our customers.  Substantially all of our installed telephone lines are capable of delivering ADSL services. As of December 31,  2010, we had approximately 4.61 million lines of ADSL and had 2.32 million ADSL customers. In addition,  the Ethernet-based FTTx system is also introduced into our access network to provide broadband services, such  as MOD, high speed internet access and VPN. As of December 31, 2010, we have constructed approximately  3.36 million FTTx ports and had 2.04 million FTTx customers. Our FTTx service can offer high-speed  broadband internet access rates up to 100 Mbps.  Domestic telecommunications network . Our domestic public switched telephone network consists of  19 message areas connected by a long distance network. As of December 31, 2010, we had 38 long distance  exchanges, which are interconnection points between our telecommunications network.  In 2010, we expanded our NGN core network capacity, accommodating 560,000 local telephone  subscribers, comprising of 448,000 Session Initiation Protocol-based, or SIP-based, and 112,000 Access  Gateway-based, or AG-based, subscribers. In 2010, we initiated a new extension of 238,100 AG-based  subscribers. AG-based subscribers will be provided with the original services. SIP-based subscribers access the  NGN core network through broadband circuits and will have access to innovative value-added services in the  future along with the original services.  Our NGN Managed IP backbone network consists of an inner core network and an outer core network. We  completed the construction of our high-speed NGN Managed IP backbone network at the end of 2010 with 12  sets of 640 Gbps gigabit switch routers for the inner core network and more than 24 sets of 640 Gbps gigabit  switch routers for the outer core network. The bandwidth of the network is approximately 550 Gbps as of the end  of 2010. We believe this network will enable us to meet the increasing demand for NGN services, such as VoIP,  and all managed services, including MOD and VPN.  We currently have intelligent networks installed over our public switched telephone networks for our  domestic long distance and international networks, as well as a local intelligent network in the Taipei, Taichung  and Kaohsiung metropolitan areas. Our intelligent network is designed to facilitate the use of value-added  services by providing more information about calls and allowing greater management of those calls.  Switching Networks  42 PART I