Endpoint Identifiers Research Articles

Novel method for transferring access control list rules to synchronize security protection in a locator/identifier separation protocol environment with cross‐segment host mobility

SummaryExtended access control lists (ACLs) are used to filter packets for network security. However, in current network frameworks, ACL rules are not transferred simultaneously with devices that move across network segments. The Internet Engineering Task Force proposed the Locator/Identifier Separation Protocol (LISP), which enables routers (xTRs) to configure ACL rules for blocking immobile endpoint identifiers (EIDs). However, when an EID moves from the original xTR to a new xTR, the ACL rules at the original xTR cannot be transferred with the EID. Thus, the new xTR lacks the corresponding ACL rules to effectively block the EID, resulting in security risks. The highlights of this study are as follows. First, a method is proposed for dynamically transferring ACL rules in LISP environments and frameworks. Second, the map‐register and map‐notify protocols were combined to encapsulate and transfer the ACL rules and thus obviate an additional process required to transfer these rules. Third, the experimental results verified that the proposed method can be used to achieve synchronized security protection in an LISP environment involving cross‐segment EID movements.

전달모드 LISP-DDT 매핑 시스템에 관한 연구

The Locator/Identifier Separation Protocol (LISP) is a new routing architecture that implements a new semantic for IP addressing. It enables the separation of IP addresses into two new numbering spaces: Endpoint Identifiers (EIDs) and Routing Locators (RLOCs). This approach will solve the issue of rapid growth of the Internet’s DFZ (default-free zone). In this paper, we propose an algorithm called the Propagated-Mode Mapping System to improve the map request process of LISP-DDT.

Bundle Protocol Header Compression

Delay Tolerant Networks (DTNs), especially the Bundle Protocol (BP), transmit data in self-contained bundles each of which carrying all necessary information to process it and route it to its destination. While this allows for long delays, link disruptions and higher loss rates and makes the BP well-suited for networks such as Wireless Sensor Networks (WSNs), it imposes a significant overhead in terms of the header sizes, as e. g. node addresses are denoted as full URIs, called Endpoint Identifiers (EIDs). While the Compressed Bundle Header Encoding introduces a special naming scheme to eradicate these URIs which reduces the header size to some extent, in this paper we present a novel, full-fledged header compression for the BP that can be applied stateless or stateful, i. e. without or with storing part of the bundle headers on forwarding nodes. The gains achievable with this approach are extensively evaluated with the simulation of bundles carefully generated from real-world network traffic on the one hand, and of realistically moving public transport vehicles with a traffic pattern often found in such Delay Tolerant Wireless Sensor Networks (DTWSNs) on the other hand.

LISP-PCHORD: An enhanced pointer-based DHT to support LISP

Aiming to efficiently support the Locator/Identifier Separation Protocol (LISP), in this paper, we present an enhanced pointer-based DHT mapping system: LISP-PCHORD. The system creates a pointer space to build on top of standard DHTs. Mappings within the pointer space are (Endpoint Identifiers (EID), pointers) where the pointer is the address of the root node (the physical node that stores the mappings) of the corresponding (EID, Routing Locators (RLOCs)) mappings. In addition to enabling architectural qualities such as scalability and reliability, the proposed LISP-PCHORD can copy with flat EIDs such as self-certifying EIDs. The performance of the mapping system plays a key role in LISP; however, DHT-based approaches for LISP seldom consider the mismatch problem that heavily damages the system performance in terms of lookup latency. In order to mitigate the mismatch problem and achieve optimal performance, we propose an optimization design method that seeks an optimal matching relationship between P-nodes (nodes within the pointer space) and the physical nodes on the basis of the given lookup traffic matrix. In order to find the optimal matching relationship, we provide two solutions: a linear programming method and a genetic algorithm. Finally, we evaluate the performance of the proposed scheme and compare it with that of LISP-DHT.

Optimal Cache Timeout for Identifier-to-Locator Mappings with Handovers

The locator/ID separation protocol (LISP) proposed for addressing the scalability issue of the current Internet has gained much interest. LISP separates the identifier and locator roles of IP addresses by end point identifiers (EIDs) and locators, respectively. In particular, while EIDs are used in the application and transport layers for identifying nodes, locators are used in the network layer for locating nodes in the network topology. In LISP, packets are tunneled from ingress tunnel routers (ITRs) to egress tunnel routers in a map-and-encapsulation manner. For this purpose, an ITR caches on demand some mappings between EIDs and locators. Since hosts roam from place to place, however, their EID-to-locator mappings change accordingly. Thus, an ITR cannot store a mapping permanently but maintains for every mapping a timer whose default value is set to a given cache timeout. If the cache timeout for a mapping is too short, an ITR frequently queries the mapping system (control plane), resulting in a high traffic load on the control plane. On the other hand, if the cache timeout for a mapping is too long, the mapping could be outdated, resulting in packet loss and associated overheads. Therefore, it is desirable to set appropriate cache timeout for mapping items. In this paper, we analytically determine the optimal cache timeout for EID-to-locator mappings cached at ITRs to minimize the control plane load while remaining efficient for mobility. The results presented here provide valuable insights and guidelines for deploying LISP.

A distributed mobility control scheme in LISP networks

The locator identifier separation protocol (LISP) has been made as an identifier-locator separation scheme for scalable Internet routing. However, the LISP was originally designed for fixed network environment, rather than for mobile network environment. In particular, the existing LISP mobility control schemes use a centralized map server to process all the control traffics, and thus they are intrinsically subject to some limitations in mobile environment, such as large overhead of mapping control traffics at central map server and degradation of handover performance. To overcome these problems, we propose a distributed mobility control scheme in LISP networks. In the proposed scheme, we assume that a mobile host has a hierarchical endpoint identifier which contains the information of its home network domain. Each domain has a distributed map server (DMS) for distributed mapping management of Endpoint Identifiers (EIDs) and Locators (LOCs). For roaming support, each DMS maintains a home EID register and a visiting EID register which are used to keep the EID-LOC mappings for mobile hosts in the distributed manner. For performance analysis, we compare the control traffic overhead (CTO) at map servers, the signaling delay required for EID-LOC mapping management, and the handover delay for the existing and proposed schemes. From numerical results, it is shown that the proposed distributed scheme can give better performance than the existing centralized schemes in terms of CTO, total signaling delay for EID-LOC mapping management, and handover delay.

Distributed Mapping Management of Identifiers and Locators in LISP-based Mobile Networks

The Locator Identifier Separation Protocol (LISP) has been proposed as an identifier-locator separation scheme for scalable Internet routing. However, LISP was originally designed in the fixed network environment rather than in the mobile network environment. In particular, the existing LISP mobility schemes are based on a centralized map server that is used as an anchor point for mobile nodes, and thus intrinsically subject to some limitations in mobile environment. In this paper, we propose a distributed mapping management of Endpoint Identifiers (EIDs) and Locators (LOCs) in mobile LISP networks. We use Routing LOC (RLOC) and Local LOC (LLOC) as locators for mobile hosts. RLOC represents the IP address of the domain gateway, and LLOC is the IP address of the access router that a host is currently attached to. For EID-LOC mapping management, each network domain has a Distributed Map Server (DMS) over its gateway. Each DMS keeps track of the EID-LOC mapping information for mobile hosts in the distributed way. The proposed scheme is also a network-based approach, in which each access router, instead of a host, performs the mapping management operations. From the performance analysis, we can see that the proposed distributed scheme can give better performance than the existing schemes in terms of the signaling delays required for EID-LOC mapping update and query operations.