Header Compression Mechanism Research Articles

Enabling Extremely Energy-Efficient End-to-End Secure Communications for Smart Metering Internet of Things Applications Using Static Context Header Compression

Smart metering IoT applications are among the most energy-critical in the current panorama. Metering sensors are battery-powered and are expected to have a lifetime exceeding ten years. In order to achieve such long operation duration, a generic header compression mechanism named Static Context Header Compression (SCHC) has been introduced and accepted as a standard by the Internet Engineering Task Force (IETF). This paper aims to demonstrate the energy savings enabled by the use of SCHC on a cellular IoT network by the means of real-life implementation and measurements. Experiments are conducted in a controlled environment for different scenarios and considering multiple parameters such as message size and radio conditions. Measurements show the high impact of this header compression mechanism, particularly when the radio conditions are bad and repetitions are used to improve the reliability of the transmission: a reduction of up to 40% in energy consumption is observed. Using SCHC over the non-IP transport mode (NIDD) of NB-IoT compared to the legacy IP mode also enables significant energy savings and allows the latency to be reduced while maintaining the interoperability provided by the IP layer.

Packet Header Compression in the Internet of Things

Abstract Because of the massive development of the Internet of Things (IoT), the quantity of remote devices associated with the Internet is estimated to touch 26 billion by 2020. This will challenge both the energy proficiency of wireless battery fuelled gadgets and the bandwidth capacities of wireless networks. One answer for both difficulties could be to use packet header compression. The primary reason for having header compression is that there is a huge amount of redundancy in the header fields of the packets owned by the same packet stream. Hence, there is a need to reduce this redundancy to make the best use of the available bandwidth so as to make the processing of data faster. This can be done by bringing the compressor and decompressor in sync with each other. To reduce the header size considerably, sending static/fixed information only initially followed by making predictions and the use of dependencies for rest of the fields fructifies. This paper reviews various existing header compression schemes, identifies the need for Robust Header Compression (ROHC) scheme and introduces the header compression of 6LoWPAN. 6LoWPAN provides header compression mechanisms to reduce the size of upper layer headers. 6LoWPAN header compression mechanisms can be used to compress the security headers as well.

Modified Simple Network Management Protocol for 6Lowpan

Simple Network Management Protocol (SNMP) is an internet standard protocol for managing devices on IP network and is one of the key components of NMS (Network management system). It is also used in a variety of application such as remote monitoring and controlling of the network nodes. Lowpan consist of large number of low-cost devices.lowpan faces several challenging issues such as small packet size, low bandwidth, low power, a large number of devices. In order to, overcome these issues, the 6lowpan was originated. The 6lowpan group has defined encapsulation and header compression mechanism that allow,ipv6 packets to be sent to and received from over lowpan based networks.6lowpan is a severely resource constrained network. Hence, existing SNMP protocol need to be modified. The 6lowpan-snmp is an extended modification of the SNMP.The SNMP is mainly used to manage a sensor node which has allocated IP address. These IP networks can be integrated with the 6lowpan by transmitting the SNMP packets over 6lowpan.this can be achieved by compressing SNMP packet and reduce the number of SNMP message over the network. This paper, tries to show effectiveness and feasibility of the proposed scheme on resource-constraint sensor network.

모바일 와이맥스에서의 효율적인 무선링크 대역폭 활용을 위한 헤더압축기법인 ROHC RTP 프로파일의 성능 분석

IP 기반 무선 광대역 서비스를 제공하는 모바일 와이맥스에서 물리적으로 제한적인 무선링크의 대역폭은 성능 저하의 큰 요인이 된다. 모바일 와이맥스 표준에서는 무선링크 대역폭의 효율적 활용을 위해 헤더 압축 기법인 PHS(Payload Header Suppression)를 정의하였으나, 제한적인 압축 가능 필드로 인해 PHS의 압축 효율성은 매우 낮다. 이에 본 논문에서는 높은 비트에러율과 긴 RTT(Round Trip Times) 및 제한적인 자원과 같은 특성을 지닌 무선 링크에 적절한 헤더 압축 기법으로 제안된 ROHC(Robust Header Compression)를 모바일 와이맥스에 적용하였을 때의 성능을 분석하고 PHS와 비교하였다. ROHC 성능에 대한 기존연구들은 무선링크에서의 비트에러에 대한 성능 분석에 초점을 맞추었으나, 맥 계층에서 에러 체크 기능을 제공하는 와이맥스와 같은 무선시스템의 경우 비트에러가 포함된 패킷이 상위 계층에 전달될 확률은 거의 없으므로 다른 측정 기준이 필요하다. 이에 본 논문에서는, 비트에러 대신 모바일 와이맥스 환경에서 발생할 수 있는 패킷 손실에 따른 ROHC의 성능 평가를 수행하였다. 다양한 ROHC 구현파라미터들이 ROHC 성능에 미치는 영향을 분석하고, ROHC와 기존의 방안인 PHS의 성능을 비교하였다. Mobile WiMAX provides wireless broadband services for data communication based on IP protocol. The limitation of physical bandwidth in the radio links may cause performance degradation in providing wireless broadband services in WIMAX. To enhance the efficiency of the radio link utilization, Payload Header Suppression (PHS) is defined as an optional header compression mechanism for mobile WiMAX. It has, however, a very limited compression capability since it has very restrictive compression fields. In this paper, hence, we assumed the application of Robust Header Compression (ROHC), a header compression scheme proposed for links characterized by high bit error ratios, long round-trip times (RTT), and scarce resource, to Mobile WiMAX, and studied its performance. Previous studies on ROHC performance merely focused on the impact of high bit error rate. However, bit error is virtually transparent to ROHC in the wireless systems like WiMAX, since the MAC provides the bit error checking function. In order to evaluate the performance of ROHC in the Mobile WiMAX environments, therefore, we evaluated the performance of ROHC with respect to the packet losses instead of bit error. We investigated the impact of the ROHC parameters that are recommended for the implementation in the ROHC and compared the performance of ROHC with PHS.

Performance comparison between VBR speech coders for adaptive VoIP applications

The introduction of new variable bit rate (VBR) speech coders has opened up new perspectives for the implementation of adaptive voice over IP (AVoIP) systems. The paper compares different VBR speech coding techniques in a scenario in which the rate of the single sources is dynamically adapted to the workload conditions. The coders compared are the AMR, the M/sup 3/ R and the G.729. Using source and rate control mechanism models, performance is evaluated in terms of loss probability, offered throughput and mean CMOS with varying numbers of sources. The use of header compression mechanisms is also evaluated.