This chapter described the various operations and services provided by the DNS protocol. These operations include queries, recursive and interative (nonrecursive); zone transfers; and dynamic update. ...I described the process known as reverse mapping, in which a normal query is used to obtain the name of a host given its IP address, and illustrated it with some examples. The chapter concluded with a brief overview of the security implications that necessarily arise from running any DNS service.
Chapter 4 describes a number of name server (DNS) types while recognizing that the majority of name servers are required to provide multiple functions.
On the Hadoop Core mailing list, a user was wondering about the way to handle a specific style of range query with MapReduce. The application had a search space and incoming search requests. In this ...chapter, we’ll look at a similar setup, as follows:
The search space dataset has the key range begin, range end and the value search space data. For simplicity’s sake, let’s assume that ranges in the search space do not overlap.The search request dataset has the key value and the value search request data.The result set for a value that is between range begin and range end has the key value and the value search request data, search space data.
One challenge in understanding the evolution of Internet infrastructure is the lack of systematic mechanisms for monitoring the extent to which allocated IP addresses are actually used. Address ...utilization has been monitored via actively scanning the entire IPv4 address space. We evaluate the potential to leverage passive network traffic measurements in addition to or instead of active probing. Passive traffic measurements introduce no network traffic overhead, do not rely on unfiltered responses to probing, and could potentially apply to IPv6 as well. We investigate two challenges in using passive traffic for address utilization inference: the limited visibility of a single observation point; and the presence of spoofed IP addresses in packets that can distort results by implying faked addresses are active. We propose a methodology for removing such spoofed traffic on both darknets and live networks, which yields results comparable to inferences made from active probing. Our preliminary analysis reveals a number of promising findings, including novel insight into the usage of the IPv4 address space that would expand with additional vantage points.
Design and implementation of windows based DSTM client Hee-Cheol Lee; Myung-Ki Shin; Hyoung-Jun Kim ...
The 6th International Conference on Advanced Communication Technology, 2004,
2004, Letnik:
2
Conference Proceeding
As the native IPv6 networks will be more extended, IPv4 in IPv6 tunneling will be needed to interconnect the isolated IPv4 networks through huge IPv6 Internet. And also the IPv6 based IPv4 tunneling ...mechanisms such as DSTM can be more needed to construct the IPv6 native network with supporting the seamless and transparent IPv4/IPv6 internetworking. But there is as yet no Windows implementation of DSTM, which is one platform where the technique would potentially be most often required. We have implemented DSTM client without any modification of TCP/IP protocol stack in Windows based platform and verified its usability through various experiments with existing applications.
Impact of IPv6 on end-user applications Raicu, I.; Zeadally, S.
10th International Conference on Telecommunications, 2003. ICT 2003,
2003, Letnik:
2
Conference Proceeding
With IPv6's maturity increasing, there is a need to evaluate the performance benefits or drawbacks for end users that the new IPv6 protocol will have compared to the well-established IPv4 protocol. ...Theoretically, the expected overhead between the two different protocols should be directly proportional to the difference in the packet's header size, and therefore the expected performance of IPv6 should be similar to IPv4. According to findings, the empirical performance difference between IPv4 and IPv6 in a real setting is much higher than anticipated. The experiment setup is the key ingredients in the findings since it demonstrates the current performance of IPv6 as delivered by commercial routers supporting IPv6 for performance metrics such as throughput and latency.
Programming challenges in network processor deployment Kulkarni, Chidamber; Gries, Matthias; Sauer, Christian ...
International Conference on Compilers, Architecture and Synthesis for Embedded Systems: Proceedings of the 2003 international conference on Compilers, architecture and synthesis for embedded systems; 30 Oct.-01 Nov. 2003,
10/2003
Conference Proceeding
Programming multi-processor ASIPs, such as network processors, remains an art due to the wide variety of architectures and due to little support for exploring different implementation alternatives. ...We present a study that implements an IP forwarding router application on two different network processors to better understand the main challenges in programming such multi-processor ASIPs. The goal of this study is to identify the elements central to a successful deployment of such systems based on a detailed profiling of the two architectures. Our results show that inefficient partitioning can impact the throughput by more than 30%; a better arbitration of resources increases the throughput by at least 10%, and localization of computation related to the memories can increase the available bandwidth on internal buses by a factor of two. The main observation of our study is that there is a critical lack of tools and methods that support an integrated approach to partitioning, scheduling and arbitration, and data transfer management for such system implementations.
In today’s world of ubiquitous mobile devices and always-on connections to the Internet, the topic of networking is of great importance. On iOS alone, a great quantity of applications make use of the ...network in one way or the other, whether using built-in systems like iCloud synchronization or GameKit’s communication framework, or by communicating directly with servers over the Internet. Moreover, the expectations of consumers often clashes with the capabilities and limitations of wide-area mobile networks such as EDGE, 3G, and HDPSA+, leaving you, the application programmer, to make the best of a high-latency, low-throughput network channel.
IPv4 architecture is well entrenched with Network Address Translation (NAT) boxes, which cause well-known problems for Peer-to-Peer (P2P) applications. IPv6 would enable end-to-end connectivity when ...deployed, but the industry has been slow in transitioning to IPv6. IPv4+4 has been suggested as an alternative NAT-extended addressing architecture, where the idea is to assign 64-bit end-to-end globally unique addresses for nodes on private address realms by concatenating the 32-bit globally routable IPv4 address of the realm (border) gateway with the 32-bit private IPv4 addresses of the nodes. While IPv4+4 addressing proposal is neat, existing IPv4+4 implementations require changes to all border gateways and end-hosts, which hinders its deployment. In this paper we show how the IPv4+4 addressing architecture can be implemented by using a modified version of the standard IPv4 Loose Source Record Route (LSRR) option. Our proposal requires no changes to existing IPv4 infrastructure (assuming all IPv4-compliant nodes implement LSRR as required by RFC 791), thus enabling seamless end-to-end communication for P2P applications. We demonstrate packet forwarding with the 64-bit IPv4+4 addresses, and illustrate how the widely-used P2P voice over IP protocol, the Session Initiation Protocol, can make use of our proposal for seamless end-to-end communication.
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