Chapter 6 Distributed systems Building secure distributed systems

Fault Tolerance and Failure recovery l The five 9’s are as much a part of security as other issues l MTBF mean-time-between-failure l MTTR Mean-time-to-repair l Fault tolerance Fail-stop machines l Redundancy l

Tools l Hardware redundancy l Group redundancy l Backup l Fallback l These are all different things that do different stuff for you

Concurrency l 2 systems running at same time Old data l Inconsistent updates l l Order of updates Deadlock l Data never converges to consistent values l Timing issues l Replay attacks l

Service Denial Attacks l Very easy to perform l Can be devastating and difficult to stop l We will discuss zombies later and how they are used to mount DOS attacks l Type of network flooding attack

Naming l l l l l Facilitate sharing Naming information is distributed The name space keeps growing Global names can still be issues Keeping naming flexible Names are used for access also It is nice when invalid names are easy to distinguish Consistency is issue KISS Bind early or late

Naming and identity l l l The author brings up many naming issues that can create problems We must consider international issues also as discussed We get assigned new “names” all the time and then people try to tie them together Interesting IPv 6 discussion Names in context

Discussion l NTP, current uses and hacks l Current state of IP addresses and IPv 6 l Different perspective of use of IPv 6 l Government request for Google search data

List of resources l five l 9’s http: //www. businesscertainty. net/2006/04/re visiting_the_nines_1. html l MTBF MTTR http: //en. wikipedia. org/wiki/MTBF l http: //en. wikipedia. org/wiki/Mean_time_to_r epair l

List of resources l Hardware redundancy http: //www. eventhelix. com/Realtime. Mantra/ Hardware. Fault. Tolerance. htm l http: //www. microsoft. com/technet/prodtechn ol/exchange/guides/E 2 k 3 High. Av. Guide/ebda 97 ad-574 a-421 d-8 d 1 b 1 bb 1 ab 70 cf 5 f. mspx? mfr=true l

List of resources l Clusters l http: //en. wikipedia. org/wiki/Computer_cluste r#Clustering_software_. 28 open_source. 29 l Fallback l http: //www. teradata. com/t/page/115417/inde x. html

List of resources l Concurrency l l l http: //en. wikipedia. org/wiki/Parallel_programming http: //en. wikipedia. org/wiki/Concurrency_(computer _science) Data l l http: //publib. boulder. ibm. com/infocenter/db 2 luw/v 8/i ndex. jsp? topic=/com. ibm. db 2. udb. doc/admin/c 0005 267. htm http: //www. microsoft. com/technet/itsolutions/cits/iw p/ibf/soldev/moibf 1_sdg_apd. mspx

List of Resources l Denial of Service attacks l l http: //en. wikipedia. org/wiki/Denial_of_service Naming l l http: //www. base. com/gordoni/web/naming. html UMTS Universal Mobile Telecommunications System l http: //www. umtsforum. org/servlet/dycon/ztumts/Live/en/umts/Resour ces_Reports_12_es

List of Resources l IPv 6 http: //www. ipv 6. org/ l http: //en. wikipedia. org/wiki/IPv 6 l