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Addressing and Address Management Allocating addresses.WHAT THE TWO VERSIONS AREThe original, whose free pool is exhausted The... Anti-Spam Technology Filtering unwanted mail.WHAT TECHNIQUES EXISTConnection-level checks: reputation, reverse names,... Anycast Networking One address, many locations.WHAT IT ISThe same address announced from several locations, with... Authoritative DNS Server Design Serving a zone reliably.WHAT RELIABILITY REQUIRESSeveral servers On separate networks In separate... Automated Server Provisioning Building machines without hands.WHAT THE STAGES AREPowering on and booting from the network... Automating Data Centre Operations Reducing manual work.WHAT TO AUTOMATEProvisioning Configuration Monitoring registration Patching... BGP Security and Route Hijacking Protecting routing.WHAT THE FUNDAMENTAL WEAKNESS ISThe protocol was designed for a trusted... Backup Infrastructure Systems that protect data.WHAT A BACKUP ISA separate copy, from a point in time, that the live... Bare-Metal Servers Physical machines without virtualisation.WHAT THEY PROVIDEAll of the hardware, with no hypervisor... Building Infrastructure for This Market Local operating realities.WHAT THE DEFINING CHALLENGE ISPower reliability.WHAT THAT... Caching Systems Beyond the Edge Application and data caching.WHERE CACHING HAPPENSThe browser A delivery network A reverse proxy... Capacity Planning for Infrastructure Growing ahead of demand.WHAT TO MEASURECurrent use, per resource The growth trend Peak against... Certificate Management at Scale Automation and lifecycle.WHAT AUTOMATED ISSUANCE PROVIDESCertificates obtained and renewed... Certificate Security and Transparency Preventing misissuance.WHAT MISISSUANCE ISA certificate issued for a name to someone not entitled... Certificates and Public Key Infrastructure Establishing trust.WHAT A CERTIFICATE CONTAINSA public key The names it is valid for Validity... Comparing Virtualisation Platforms The main options.WHAT THE ESTABLISHED COMMERCIAL PLATFORM PROVIDESMature management Live... Configuring Caching Correctly Controlling what is stored and for how long.WHAT CONTROLS CACHINGResponse headers stating how... Container Technology in Infrastructure Isolation without full virtualisation.WHAT A CONTAINER ISA process isolated by kernel features,... Control Panel Infrastructure The management layer.WHAT A CONTROL PANEL PROVIDESAccount provisioning File, database and mail... DNS Architecture in Depth How resolution actually works.WHAT THE HIERARCHY ISRoot servers, knowing where each top-level... DNS Architecture: Everything That Matters, Briefly The summary.PROPAGATION IS CACHES EXPIRING, NOT DATA SPREADINGThere is nothing to accelerate.... DNS Security Threats What goes wrong.CACHE POISONINGInjecting false data into a resolver's cache, directing users... Data Centre Network Topologies How the internal network is arranged.WHAT THE TRADITIONAL ARRANGEMENT WASThree tiers: access,... Data Centre Networking: Everything That Matters, Briefly The summary.MODERN DESIGNS OPTIMISE FOR TRAFFIC BETWEEN MACHINES, NOT IN AND OUTMeasure actual... Data Centre Security Controls Protecting the facility and its systems.WHAT PHYSICAL CONTROLS COVERPerimeter, building, zone,... Database and Data Replication Keeping copies consistent.WHAT REPLICATION DOESMaintains copies of data on several systems.WHAT... Declaring Infrastructure in Version Control Declaring infrastructure in files.WHAT IT MEANSInfrastructure defined in files, versioned,... Delivery and Caching: Everything That Matters, Briefly The summary.A LOW CACHE HIT RATE MEANS THE DELIVERY NETWORK IS ACHIEVING LITTLEQuery strings... Designing High Availability Clusters Continuing through failure.WHAT A CLUSTER ISSeveral machines cooperating so that a service... Disaster Recovery Planning Preparing for serious loss.WHAT DISASTER RECOVERY ADDRESSESLoss of a site, a system, or data,... Documenting Network and Infrastructure Estates Recording what exists and why.WHAT TO DOCUMENTWhat systems exist, and what each is for How they... Email Authentication Records Proving mail is legitimate.WHAT THE THREE MECHANISMS AREA record declaring which servers may send... Email Deliverability Getting mail accepted.WHAT DETERMINES WHETHER MAIL ARRIVESThe sending address's reputation The... Email Infrastructure: Everything That Matters, Briefly The summary.REJECT AT THE TRANSACTION RATHER THAN ACCEPTING AND BOUNCINGAccepting then bouncing... Enabling Modern Protocols Practical deployment.WHAT IS REQUIREDA server supporting the protocol Encryption, which both... Handling Abuse and Compromised Accounts Responding to problems on your network.WHAT ABUSE LOOKS LIKEOutbound mail floods Phishing pages... Hardware and Software RAID Where the work happens.WHAT HARDWARE RAID ISA dedicated controller managing the array.WHAT IT... High Availability and Recovery: Everything That Matters, Briefly The summary.A PASSIVE NODE THAT HAS NEVER SERVED MAY NOT WORK WHEN NEEDEDTest failover... High Availability for Front-End Services Removing single points of failure.WHAT THE PROBLEM ISA load balancer distributing traffic is... How Content Delivery Networks Work Serving from close to the user.WHAT THEY AREDistributed networks of servers holding copies of... How Email Infrastructure Works The components and the flow.WHAT THE COMPONENTS AREA submission service, accepting mail from... How Internet Service Providers Are Built The provider network.WHAT A PROVIDER NETWORK CONSISTS OFAccess: how customers connectAggregation:... How TLS Works Encrypting connections.WHAT IT PROVIDESConfidentiality: traffic cannot be readIntegrity: traffic... Infrastructure Change Management Controlling what is altered.WHY IT MATTERSMost infrastructure incidents follow a change.WHAT... Infrastructure Incident Response When something breaks.WHAT TO DO FIRSTEstablish scope: what is affected, and who.WHAT TO DO... Infrastructure Monitoring and Alerting Knowing the state of everything.WHAT TO MONITORAvailability, from outsideCapacity: processor,... Internet Architecture: Everything That Matters, Briefly The summary.ROUTING IS POLICY BEFORE IT IS GEOGRAPHYThe shortest path is not chosen; the... Internet Exchange Points Where networks meet.WHAT AN EXCHANGE POINT ISA facility where many networks connect to a shared... Internet and Advanced Infrastructure: Everything That Matters, Briefly The whole category in one page.ROUTING IS POLICY BEFORE IT IS GEOGRAPHYThe commercially preferred... Load Balancing Fundamentals Distributing traffic.WHAT IT DOESDistributes requests across several servers, and stops sending... Mail Access Protocols How users read mail.WHAT THE TWO APPROACHES AREOne downloading messages and typically removing... Mail Server Operations Running mail reliably.WHAT TO MONITORQueue size and age Deferred mail Rejection rates... Managing Address Reputation Keeping your network trusted.WHY IT MATTERSYour addresses carry a reputation, and a poor one... Measuring and Diagnosing Internet Paths Finding where the problem is.WHAT TO ESTABLISH FIRSTWhether the problem affects one destination... Migrating Customers Between Servers Moving accounts without disruption.WHY IT HAPPENSHardware replacement Rebalancing load Upgrading... Modern DNS Privacy and Transport Encrypted resolution.WHAT THE PROBLEM ISTraditional DNS queries are sent unencrypted and visible... Monitoring Network Infrastructure Watching the fabric.WHAT TO MONITORLink status and utilisation Error, discard and retransmission... Monitoring a Hosting Fleet Watching many machines.WHAT TO MONITOR PER MACHINEAvailability, from outside Load, memory,... Network Attached Storage Storage served over a network.WHAT IT ISStorage presented as file shares over a network.WHAT... Network Automation Configuring at scale.WHY MANUAL CONFIGURATION FAILS AT SCALEDevices drift apart, mistakes are... Network Segmentation Separating traffic.WHY IT MATTERSFlat networks allow anything to reach anything, so one... Operating DNSSEC Safely Avoiding self-inflicted outages.WHAT CAUSES MOST DNSSEC OUTAGESExpired signatures Key rollover... Orchestrating Containers at Infrastructure Scale Running containers at scale.WHAT ORCHESTRATION PROVIDESScheduling containers across machines... Out-of-Band Management Networks Reaching equipment when the network fails.WHAT IT ISA separate network reaching management... Outbound Mail Abuse Control Preventing your servers becoming a source.WHY IT MATTERS MOST TO A HOSTING PROVIDEROne... Protecting Against Volumetric Attacks Absorbing floods.WHAT THEY AREAttempts to overwhelm a service or its connection with traffic.WHY... Protocols and Transport: Everything That Matters, Briefly The summary.EACH HTTP VERSION ADDRESSED THE BOTTLENECK THE LAST ONE EXPOSEDVersion two removed... Recursive Resolver Operation Serving queries for clients.WHAT A RESOLVER DOESAccepts queries, performs resolution, caches... Redundancy for Hosting Services Removing single points of failure.WHAT TO IDENTIFYEvery component whose failure affects... Resource Isolation on Shared Servers Keeping customers apart.WHAT TO LIMIT PER ACCOUNTProcessor time Memory Concurrent processes... Running BIND The established nameserver.WHAT IT ISThe most widely deployed nameserver, capable of both... Running Dovecot Mail storage and access.WHAT IT ISA server providing mail access, with mailbox storage and... Running Exim An alternative transfer agent.WHAT IT ISA transfer agent with a single configuration file and a... Running Postfix A widely used transfer agent.WHAT IT ISA modular transfer agent, designed for security and... Running PowerDNS A database-backed nameserver.WHAT DISTINGUISHES ITSeparation of the authoritative server, the... Running a Hosting Platform: Everything That Matters, Briefly The summary.PER-ACCOUNT LIMITS ARE WHAT MAKE SHARED HOSTING WORKWithout them one site under load... SMTP in Practice The transfer protocol.WHAT IT DOESTransfers mail between servers, and accepts it from... Scaling a Hosting Platform Growing the infrastructure.WHAT CONSTRAINS GROWTH FIRSTStorage performance, usually.WHAT ELSE... Session Persistence and Stateless Design Handling state behind a balancer.WHAT THE PROBLEM ISA user's requests may reach different... Shared Hosting Architecture How shared hosting is built.WHAT IT ISMany customers' sites served from one machine, isolated... Storage Area Networks Block storage over a network.WHAT IT ISStorage presented as block devices, as though locally... Storage Infrastructure: Everything That Matters, Briefly The summary.RAID IS NOT A BACKUPIt protects against drive failure, not deletion, corruption,... Storage Performance and Capacity Planning Sizing and measuring.WHAT TO MEASUREOperations per second Throughput Latency Queue depthWHAT... Switching and Fabric Design Building the internal network.WHAT A TOP-OF-RACK SWITCH DOESConnects the servers in one rack, and... Testing and Verifying Backups Proving they work.WHY IT MATTERS MOSTAn untested backup is an assumption, and the assumption... The Evolution of HTTP From one version to the next.WHAT THE ORIGINAL VERSION DIDOne request per connection, then the... The Structure of the Internet Networks of independent networks.WHAT IT ISTens of thousands of independently operated networks,... Understanding BGP The protocol that holds the internet together.WHAT IT DOESExchanges reachability information... Understanding DNSSEC Authenticating DNS responses.WHAT PROBLEM IT SOLVESDNS responses can be forged, and there is... Understanding HTTP/2 Multiplexing over one connection.WHAT IT PROVIDESSeveral concurrent streams over a single... Understanding Internet Capacity and Congestion Where slowness comes from.WHAT DETERMINES PERCEIVED SPEEDBandwidth: how much can be... Understanding QUIC and HTTP/3 A new transport.WHAT QUIC ISA transport protocol built on datagrams, providing reliability,... Understanding RAID Combining drives.WHAT IT DOESCombines several drives for capacity, performance, resilience, or a... Understanding Reverse Proxies A server in front of servers.WHAT IT ISA server accepting requests on behalf of backends, and... Understanding Server Virtualisation Machines within machines.WHAT IT ISRunning several complete operating systems on one physical... Understanding Transit and Peering How networks exchange traffic.WHAT TRANSIT ISPaying a larger network to carry your traffic to the... Virtual Machine Management Day-to-day operation.WHAT TO STANDARDISETemplates, from which machines are created Naming... Virtual Private Servers Selling virtual machines.WHAT A VPS ISA virtual machine sold to a customer, with root access.WHAT... Virtualisation: Everything That Matters, Briefly The summary.OVERCOMMIT PROCESSORS MODERATELY AND MEMORY VERY CAUTIOUSLYExhausting memory causes... Web Application Firewalls and Edge Security Filtering at the edge.WHAT A WEB APPLICATION FIREWALL DOESInspects requests and blocks those...
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