Experiences in implementing an experimental wide-area GMPLS network

Xiangfei Zhu, Xuan Zheng, Malathi Veeraraghavan
2007 IEEE Journal on Selected Areas in Communications  
In this article, we describe our experiences in implementing an experimental wide-area GMPLS network called CHEETAH (Circuit-Switched End-to-End Transport Architecture). The key concept is to add a complementary end-to-end circuit based service with dynamic call-by-call bandwidth sharing to the connectionless service already available to end hosts via the Internet. The current CHEETAH experimental network consists of off-the-shelf GMPLS-capable SONET switches (with Ethernet interfaces) deployed
more » ... at three locations, Research Triangle Park, North Carolina, Atlanta, Georgia, and Oak Ridge, Tennessee. We describe our solutions to various problems relating to control-plane design, IP addressing and control-plane security. We designed and implemented a CHEETAH software package to run on Linux end hosts connected to the CHEETAH network. Among other functions, this software package includes an RSVP-TE module to enable end users and applications to dynamically initiate requests for dedicated end-to-end circuits and receive/respond to requests for circuits. We present measurements for typical end-to-end circuit setup delays across this network. For example, end-to-end circuit setup delay from a Linux end host in NC to a host in Atlanta is 166ms. I. INTRODUCTION There is a growing interest in experimenting with optical networking technologies to meet the communication needs of applications in various science projects in the fields of high energy and nuclear physics, astrophysics, molecular dynamics, earth science and genomics. To support their research in these various fields, scientists not only require high-speed wide-area connectivity for 2 rapid movement of massive data sets, but also predictable (rate-/delay-guaranteed) connectivity for remote visualization and remote control of computations and instruments. There is a recognition in the networking research community that both these requirements (high-speed and predictable service) can be met with Generalized Multi-Protocol Label Switched (GMPLS) networks. GMPLS networks include Time Division Multiplexed (TDM) Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) networks, Wavelength Division Multiplexed (WDM) networks, and Space Division Multiplexed (SDM) networks. Using OC192 (10Gb/s) SONET interfaces or 10GbE (10Gb/s Ethernet) interfaces, several GMPLS testbeds [1]-[7] have been created to meet the high-speed needs of scientific applications. Since SONET/SDH, WDM, and SDM technologies are circuit-switched, these networks also meet the predictable service requirements of scientific applications. Given that the geographically distributed scientists and resources (computation, storage, visualization, and instruments) are fairly large in numbers, it becomes cost prohibitive to build dedicated networks for each scientific project. Instead, the high-capacity links of these networks need be shared dynamically. A set of control-plane protocols has been defined for GMPLS networks to enable such dynamic sharing of bandwidth on a call-by-call basis [8] . One of these GMPLS control-plane protocols, called signaling protocol, is used to request and release circuits on an as-needed basis. A commonly implemented GMPLS signaling protocol is Resource ReSerVation Protocol -Traffic Engineering (RSVP-TE) [9]. In this paper, we describe an experimental wide-area GMPLS network called CHEE-TAH that was deployed to meet the above-described needs of scientific applications [10] [11] . CHEETAH stands for "Circuit-switched High-speed End-to-End Transport ArcHitecture." The CHEETAH network consists of "Ethernet-SONET circuit-based gateways." An "Ethernet-SONET circuit-based gateway" is a network node that has Ethernet interface cards and SONET interface cards, and can be programmed to crossconnect any port on an Ethernet interface card to an equivalent-rate time-division multiplexed SONET signal on any port of the SONET interface cards. Technologies to transparently carry Ethernet frames within SONET frames have been defined and implemented in Ethernet-SONET circuit-based gateways. Given that most end host 3 network interface cards (NICs) are Ethernet based, these circuit-based gateways are critical to realizing our goal of connecting distant end hosts with wide-area dedicated circuits. An end-toend circuit consists of Ethernet segments at the edges mapped to SONET circuits (carrying the Ethernet signals transparently) through metro-/wide-area segments. We chose this combination of Ethernet and SONET for our experimental testbed to ease technology transfer to production networks in which Ethernet dominates LANs and SONET dominates MANs/WANs. By using GbE and 10GbE interfaces in hosts and gateways, and SONET based circuit-switched service in the WAN, CHEETAH meets both the high-speed and predictable service requirements of scientific applications. To meet the dynamic bandwidth-sharing requirement, CHEETAH is built with switches and gateways that implement GMPLS control-plane protocols. We describe several interesting problems we encountered in the design and implementation of the CHEETAH network, and our solutions to these problems. Our design philosophy is to select solutions that will allow for the scalability of the CHEETAH network and its interconnection to other GMPLS networks. Our long-term goal is to create a global-scale connection-oriented internetwork in which bandwidth sharing is based on dynamic call-by-call reservations to complement the unreserved bandwidth-sharing service available in today's Internet. These goals lead us to recommend the use of IPv6 static public IP addresses for most of the interfaces in a GMPLS network, the use of Domain Name System (DNS) to perform wide-area IP-to-MAC address resolution, the use of dynamic updates to IP and Address Resolution Protocol (ARP) tables at end hosts after the setup/release of wide-area Ethernet-SONET-Ethernet circuits, the use of the Internet as the control-plane network, and the use of IPsec to secure the control plane. To bring the benefits of CHEETAH service to scientists without requiring their deliberate participation in the invocation of this service, we implement a software package called CHEE-TAH software for Linux end hosts, and provide a CHEETAH-API (Application Programming Interface) for application programmers. For example, by integrating this API into an FTP server, such as vsftpd [12], a scientist using vsftpd would enjoy the high-speed and predictable CHEETAH service while being unaware that the vsftpd program has dynamically invoked the setup of a dedicated end-to-end CHEETAH circuit prior to executing data transfers. The Openswan 198.124.42.20 End host zelda4 Openswan 128.109.34.20 End host wukong Internet Internet Control-plane links Data-plane links IPsec tunnels 130.207.252.136 128.109.34.19 198.124.42.3 Ethernet control port: 198.124.42.2 (routerID/switchIP: 198.124.43.2) Ethernet control port: 130.207.252.2 (routerID/switchIP: 130.207.253.2) Ethernet control port: 128.109.34.2 (routerID/switchIP: 128.109.35.2)
doi:10.1109/twc.2007.026906 fatcat:mzegbs7oozesrg3zotozz4m4ci