Network Working Group P. Kim Internet-Draft Korea Polytechnic University Intended status: Experimental Expires: January 1, 2019 July 01, 2018 A Bandwidth Aggregation Scheme on Mobile Network with Multi-Interfaced Router draft-pskim-banana-mobilenetwork-mir-00 Abstract This draft considers a packet distribution scheme for bandwidth aggregation on the mobile network with a multi-interfaced router (MIR). In the proposed scheme, the MIR with multiple heterogeneous wireless network interfaces effectively and fairly distributes packets over end-to-end multi-path through multiple network interfaces. Each network interface is considered to have a distribution counter associated with corresponding end-to-end path. This distribution counter varied by both weighted capacity and distributed packets is used to determine if a network interface has enough credits to distribute incoming packets on corresponding end-to-end path. As a useful design parameter, the capacity unit can be shown to make the performance of the proposed scheme as good as possible. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on January 1, 2019. Kim Expires January 2, 2019 [Page 1] Internet-Draft Bandwidth Aggregation Scheme July 2018 Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Proposed Scheme . . . . . . . . . . . . . . . . . . . . . . . 3 2.1 Design Parameters . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Operation Procedure and Example . . . . . . . . . . . . . . . 4 2.3 Performance Indices and Useful Design Parameters. . . . . . . 5 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 4. References . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.1. Normative References . . . . . . . . . . . . . . . . . . 6 4.2. Informative References . . . . . . . . . . . . . . . . . 7 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 7 1. Introduction The BANdwidth Aggregation for Network Access (BANANA) BoF was chartered to develop solution(s) to support dynamic path selection on a per-packet basis in networks that have more than one point of attachment to the Internet. Bandwidth Aggregation consists of splitting local traffic across multiple Internet links on a per-packet basis, including the ability to split a single flow across multiple links when necessary[1][2]. This draft considers the mobile network with a multi-interfaced router (MIR)[3][4]. In addition, to consider the heterogeneous wireless network environment, the MIR can be assumed to have multiple heterogeneous wireless network interfaces. Therefore, the MIR establishes simultaneously multiple paths to the Internet through external wireless interfaces such as wireless local area network (WLAN) and wireless wide area network (WWAN) with high mobility and wide coverage. However, due to bandwidth constraints of multi-path through external wireless interfaces, the MIR might Kim Expires January 1, 2019 [Page 2] Internet-Draft Bandwidth Aggregation Scheme July 2018 require a bandwidth aggregation to get sufficient bandwidth for MNs' demanding inside a mobile network. As shown in [5], the bandwidth aggregation requires generally several functions such as bandwidth estimation, packet distribution, packet reordering, etc. Among them, this draft focuses on the packet distribution scheme which effectively and fairly distributes packets on the appropriate end-to-end path through the corresponding network interface. Therefore, this draft proposes a packet distribution scheme on the MIR with heterogeneous wireless network interfaces for mobile networks. Since the MIR is likely to have limited resources compared with a general router, the proposed scheme adopts the frame-based behavior that has lower complexity than the priority-based behavior. In the proposed scheme, the MIR with multiple heterogeneous wireless network interfaces effectively and fairly distributes packets over end-to-end multi-path. Each network interface is considered to have a distribution counter associated with the corresponding end-to-end path. This distribution counter is used to determine if a network interface has enough capacity to distribute packets on the corresponding end-to-end path. The distribution counter can get credits by the weighted capacity in bytes. The weighed capacity is operated at the byte level and is added more to the distribution counter with higher weight than that with less weight. On the other hand, the distribution counter is decreased by the size of packets being distributed. Thus, the distribution counter for each network interface is varied by distributed packets as well as weighted capacity. In the proposed scheme, performance indices can be defined by ratio and amount of distributed packets, packet loss, and throughput. The capacity unit is shown to be a useful design parameter to make the performance of the proposed scheme as good as possible. 2. Proposed Scheme This draft considers the mobile network where the MIR has multiple heterogeneous wireless network interfaces. The MIR establishes multiple communication paths to the Internet through external wireless interfaces such as WLAN and WWAN with high mobility and wide coverage. In this mobile network environment, a fair packet distribution scheme on the MIR with heterogeneous wireless network interfaces is proposed for mobile networks. 2.1 Design Parameters The MIR distributes packets effectively and fairly on the appropriate end-to-end path through the corresponding network interface. Each network interface is considered to have a distribution counter associated with the corresponding end-to-end path. This distribution Kim Expires January 1, 2019 [Page 3] Internet-Draft Bandwidth Aggregation Scheme July 2018 counter is used to determine if a network interface has enough capacity to distribute packets on the corresponding end-to-end path. The distribution counter can get credits by the weighted capacity in bytes. The weighted capacity is defined by Weighted capacity = Capacity unit*Weight. The capacity unit in bytes is a useful design parameter and thus can affect on the performance of the proposed scheme. The weight is determined proportionately from the estimated available bandwidth of end-to-end paths. The weighed capacity is operated at the byte level and is added more to the distribution counter with higher weight than that with less weight. On the other hand, the distribution counter is also decreased by the size of packets being distributed. Thus, the distribution counter for each network interface is varied by distributed packets as well as weighted capacity. 2.2 Operation Procedure and Example The operation procedure for each round is as follows. For the first path, packets are distributed when the distribution counter is greater than the incoming packet's size. If it is lower, the distribution counter is increased by the weighted capacity and then the incoming packet is distributed on the current path. Then the distribution counter is decreased by the size of packet being distributed. If the distribution counter is still lower than the incoming packet's size, the incoming packet held back until the proposed scheme moves on the next path. After visiting all paths, the round is finished. The above operation procedure in next round is repeated when there are incoming packets. As an example, the MIR is assumed to have three heterogeneous wireless network interfaces and thus there are three communication paths. These paths are called the Green (high bandwidth), Yellow (medium bandwidth), Red (low bandwidth) paths, respectively. Since this paper focuses on the packet distribution scheme, available bandwidths for three paths through corresponding interfaces are assumed to have fixed weight ratio 4:2:1. The capacity unit is set by 256 bytes and thus these paths have weighted capacity 1024, 512, 256 bytes, respectively. All initial values of distribution counters, denoted by DCg,y,r, and total amount of distributed packets, denoted by ADPg,y,r, for three paths are set with 0. There are four kinds of packet type with different sizes such as 256, 512, 768, 1024 bytes. Incoming packets are waiting to be distributed to the most appropriate path. A(1024) <- B(256) <- C(768) <- D(512) <- E(768) Kim Expires January 1, 2019 [Page 4] Internet-Draft Bandwidth Aggregation Scheme July 2018 The 1st round is operated. At Green path, the weighted capacity is added and thus the distribution counter, DCg, is 1024. Then, since the DCg is not less than the incoming packet's size (1024 bytes), the incoming packet 'A' is distributed to Green path and thus DCg=0. Currently, total amount of distributed packets to Green path, ADPg, is 1024 bytes. At Yellow path, the weighted capacity is added and thus DCy=512. Then, since the DCy is not less than the incoming packet's size (256 bytes), the incoming packet 'B' is distributed to Yellow path and thus DCy=256. Currently, ADPy=256. At Red path, the weighted capacity is added and thus DCr=256. Then, since the DCr is still less than the incoming packet's size (768 bytes), move to Green path. Currently, ADPr=0. The 1st round is done. Then, the 2nd round is operated. At Green path, since the DCg is less than the incoming packet's size (768 bytes), the weighted capacity is added and thus DCg=1024. Then, the incoming packet 'C' is distributed to Green path and thus DCg=256. Currently, ADPg=1792. At Yellow path, since DCy is less than the incoming packet's size (512 bytes), the weighted capacity is added and thus DCy=768. Then, the incoming packet 'D' is distributed to Yellow path and thus DCy=256. Currently, ADP =768. At Red path, since DCr is less than the incoming packet's size (768 bytes), the weighted capacity is added and thus DCr=512. Then, the incoming packet 'E' is distributed to Green path and thus DCg=0. Currently, ADPr=512. The 2nd round is done. The operation procedure in next round is repeated when there are incoming packets. 2.3 Performance Indices and Useful Design Parameters There can be four performance indices in the proposed scheme; ratio of distributed packets, amount of distributed packets, packet loss and throughput. Of course, the throughput can be improved as many packets are distributed. However, the improvement of the throughput does not have the meaning if the packet loss increases. Performance Index Objective -------------------------------------------------------------------- Ratio of distributed packets Distributing packets fairly according to the weight ratio of each end-to-end path Amount of distributed packets Distributing packets as many as possible over each end-to-end path Packet loss Minimizing lost packets on each end-to-end path Throughput Maximizing the average rate of successful packet delivery on each end-to-end path -------------------------------------------------------------------- Kim Expires January 1, 2019 [Page 5] Internet-Draft Bandwidth Aggregation Scheme July 2018 As mentioned before, the capacity unit is a useful design parameter to determine weighted capacity that affect on four performance indices mentioned before. Too big value of the capacity unit can introduce excessive credits for end-to-end paths, which means that network paths have enough credits to distribute packets. Thus, incoming packets are more likely to be distributed simultaneously on every path each round, which cannot provide fair distribution according to weights for network paths. Thus, the ratio of distributed packets can be degraded. In addition, since packets can be distributed too many over each end-to-end path, the performance for packet loss can be degraded. Of course, since packets are distributed too many over each end-to-end path, the throughput can be improved. However, as mentioned before, the improvement of the throughput does not have the meaning since the packet loss increases. On the other hand, too small value of the capacity unit can introduce deficient credits for end-to-end paths, which means that end-to-end paths do not have enough credits to distribute packets. Thus, incoming packets are less likely to be distributed on every paths each round, which can thus degrade the amount of distributed packets. In addition, since the amount of distributed packets over each end-to-end path is not much, the throughput can be degraded whereas the packet loss can decrease. Therefore, the important issue here is how to choose an appropriate capacity unit to make the performance of the proposed scheme as good as possible. 3. IANA Considerations This document has no IANA actions. 4. References 4.1. Normative References [1] N. Leymann, C. Heidemann, et al, "BANdwidth Aggregation for interNet Access (BANANA) The Control Protocol of Bonding Tunnels", draft-leymann-banana-signaling-02, work in progress. [2] N. Leymann, C. Heidemann, et al, "BANdwidth Aggregation for interNet Access (BANANA) The Data Plane of Bonding Tunnels", draft-leymann-banana-data-encap, work in progress. [3] M. Blanchet and P. Seite, "Multiple Interfaces and Provisioning Domains Problem Statement", IETF RFC 6418, November 2011. [4] M. Wasserman and P. Seite, "Current Practices for Multiple-Interface Hosts", IETF RFC 6419, November 2011. Kim Expires January 2, 2019 [Page 6] Internet-Draft Bandwidth Aggregation Scheme July 2018 4.2. Informative References [5] K. Habaka, K. A. Harras, M. Youssef, "Bandwidth aggregation techniques in heterogeneous multi-homed devices : A survey", Computer Networks, vol. 92, pp. 168~188, 2015. Author's Address Pyungsoo Kim Department of Electronics Engineering, Korea Polytechnic University, 2121 Jungwang-Dong, Shiheung City, Gyeonggi-Do 429-793 KOREA Phone: +82 31 8041 0489 EMail: pskim@kpu.ac.kr Kim Expires January 1, 2019 [Page 7]