The Definitive Guide on Full Packet Capture & Analysis across Networks

Packet-level visibility has become crucial for managing the complexity of modern network infrastructure and securing an expanded cyber attack surface. As enterprises adopt cloud services, Internet of Things, and support remote workers – the volume of devices, traffic, and threats continues rising exponentially.

Let‘s explore the top solutions for unlocking packet analysis to meet critical networking monitoring and security needs.

Why Packet Capture and Inspection Matters

  • Overall IP traffic estimated to grow at 26% CAGR nearing 4.2 ZB per year by 2022
  • DDoS attacks increasing over 60% year over year often saturating network capacity
  • Over 80% of cyber exploits leverage network communications at some stage
  • 57% of breaches took months to detect pointing to gaps in visibility

To keep up with bandwidth demand and combat evolving threats, network packet capture and analysis offers an essential line of defense along with crucial troubleshooting capabilities.

As packets transmit information across networked devices, real-time inspection provides definitive proof helping answer:

  • Is sensitive data actually getting encrypted before leaving perimeter?
  • Did attack payload match IOCs from latest threat intel?
  • What systems does this malware covertly communicate with?
  • Why do VoIP calls drop 30 minutes into conference calls?

This guide will arm you with the knowledge to evaluate solutions matching capability against budget and expertise. Let‘s break down key considerations when adopting packet analysis platforms:

Core Capabilities

  • Performance Stats – baseline traffic profiles by location, system and protocol
  • Anomaly Detection – identify unknown threats from network behavior patterns
  • Diagnostics – troubleshoot applications, infrastructure health issues
  • Network Forensics – reconstruct security narratives after incident
  • Regulatory Compliance – demonstrate controls for protocols like finance
  • Root Cause Analysis – pinpoint source of errors like loss and latency

Technical Planning

  • Tapped vs Spanned Links – directly inspect traffic vs make copy available
  • Network Hardware – align sensors, storage and analytics
  • Metadata – accurately classify user, system, location traits
  • Data Life-cycle – balance monitoring window vs retention policy
  • Scalability – upgrade crypto, memory, storage for capacity
  • Virtualization – leverage NFV across on-prem or cloud

Now let‘s explore leading commercial and open source packet capture and analysis solutions fulfilling today‘s diverse feature demands while fitting into technology budgets big and small!

Colasoft Capsa

Capsa packs an impressive range of monitoring, analysis and troubleshooting capabilities into a unified offering suitable for networks small, medium and large.

The solution sets itself apart with built-in expert analytics able detect anomalies and some unknown threats without extensive security analyst input. Automatic diagnostic routines help shorten Mean Time to Resolution when tackling performance issues or glitches slowing daily operations.

Key Highlights

  • Scheduler engine – configure routine packet captures to guaranteed nothing gets missed
  • 1800+ protocol decoders – decode traffic from traditional IP to cutting edge IoT standards
  • Anomaly detection – surface abnormal traffic spikes, suspicious connection attempts
  • Automated diagnostics – instantly tap knowledge database to pinpoint known problems and recommend next steps
  • Custom scripting – manipulate packet captures using Python interfaces
  • Pervasive sensors – single console visibility combining IT infrastructure and key operational technology assets

Use Cases

  • Show proof of PCI DSS controls safeguarding credit card data transfers
  • Map true application dependencies irrespective of port numbers
  • Establish utilization baseline before next Refresh Cycle

Capsa Enterprise‘s distributed architecture allows large organizations to tap into as much packet data as their infrastructure can handle – while leveraging central analysis and reporting.


This quintessential open source packet sniffer underpins a myriad of traffic debugging, analysis, and forensics capabilities leveraging the highly extensible libpcap library.

Working via the Linux/Unix command line, TCPDump surfaces raw packet capture output for redirection or even processing with scripts/plugins.

Let‘s see some example usage:

tcpdump -i eth0 -w mycap.pcap

This captures all packets seen on the eth0 interface to dump into mycap.pcap wireshark compatible output.

We can filter to specific hosts, ports or just UDP as seen next:

tcpdump -w myfiltered.pcap udp port 53

This writes only UDP DNS queries from port 53 into a separate file.

Core Features

  • Lightweight – consumes less resources so can often run passively
  • Flexible export – save captures or redirect output to other programs
  • Script integration – manipulate output with languages like Python
  • Wire speed on modern NICs – keep up with 10, 40 Gbps interfaces
  • BPF integration – craft advanced packet filters signal relevant data
  • Cross platform – consistent capabilities across Unix, Linux, macOS

TCPDump has been a packet tapping staple for over 30 years with no signs of slowing down!

Paessler PRTG

PRTG has earned IT enthusiasts mindshare as the highly customizable framework for monitoring everything infrastructure.

Besides mapping device status from traditional servers to IoT gear using SNMP among other protocols, PRTG taps into packet data flows to provide a correlational view tying trouble alerts, utilization metrics and actual user experience impact together.

Major Features

  • Smart mapping – auto detect devices across locations and visualize status on topology dashboards
  • Scalable licensing – grow sensors with network size predictably via tiered commercial packages or free
  • Packet flow sensor – surface network conversation metadata between systems providing unique traffic profiling
  • Threshold alerts – configure alarm triggers when key metrics exceed danger levels
  • Historic reporting – analyze trends to baseline expected load, inform capacity planning

With efficient distributed design and fail over capabilities, PRTG readily scales packet capture capabilities to thousands of desired vantage points. The saved flows and session data then facilitate drilling down to client-server transaction views.

Real World Use Cases

  • A cloud hosted VPN branch runs fine for 2 hours then mysteriously cuts out. Packet logs pin issue to site border router needing ACL update for revised corporate IPSec pools.
  • Diagnose why video conferencing performance suffers intermittent glitches. Packet capture traces root cause to unexpected multicast traffic from HVAC system on same subnet.

PRTG Network Monitor offers perhaps the most seamless user experience transitioning organizations from first packet capture trials to full security and performance monitoring deployments.


The powerful Swiss army knife of packet analysis. Wireshark‘s expert oriented interface does present a learning curve for carrying out advanced packet capture and analysis. But the breadth, depth, and quality of inspection make it well worth the effort to add to any network or security toolbox.

Wireshark‘s legacy over 20 years has solidified its position as the protocol analysis tool leveraged by expert practitioners across the industry.

Notable Features

  • Over 3000 protocol dissectors – parse traffic from traditional TCP/IP to modern VoIP, storage and messaging standards
  • Cross platform support across Windows, Linux, and macOS – consistent workflows across client endpoint, server racks and network appliances
  • Advanced TCP analysis – surface symptoms of issues like packet loss, latency, stalled data flows
  • GeoIP localization – understand where remote users, cloud hosted assets reside
  • Extensible architecture – tap into vast plugin ecosystem for decoding obscure protocols or crafting custom workflows in Python and Lua

Common Troubleshooting and Debug Scenarios

  • Packet loss exceeds 1% on critical app server uplink causing random user timeout issues. Net admin leverages Wireshark ioGraph capabilities to visualize retransmissions and missing sequence gaps. Root cause traced to bad memory slot in core Nexus switch corrected with replacement.
  • Security analyst needs definitive proof new IPSec VPN tunnels actually encrypt traffic end to end before passing compliance audit. Wireshark is fired up on gateway endpoints confirming protocol headers, ciphers, and tunnel metadata indicate encryption active across the wire.

Wireshark 3.6 is better than ever for tapping into network conversations – with baked in export packet dissections to JSON for elevating analysis.


Arkime delivers security-enhanced packet capture and analysis for the world‘s most demanding enterprise environments.

The solution focuses on four core design principles:

  • Visibility – Petabyte scalable retention of packets in standard PCAP format
  • Speed – Optimized back-end stores 100% of traffic from 10, 40, even 100Gbe links
  • Security – Encrypted storage protects captured network data end to end
  • Simplicity – Docker containers speed deployment with backend handling data and scaling complexity

Arkime really shines for organizations needing to not just monitor overall bandwidth patterns but pull up specific transactions on demand – even those dating months or years. User activity linking correlates identities to traffic enabling threat hunters to pivot across historical data.

Top Features

  • Scalable retention – store PB scale packets with efficient single-instance architecture
  • Replay traffic – retrieve captures matching sophisticated filters for forensic investigation
  • User activity linking – tie username metadata to clients, devices, apps communication
  • Sub-second lookups – quickly scan entire archive matching security IOCs
  • REST API – integrate context from network events into custom security orchestration

Real World Applications

  • Cloud access security broker alerts on anomalous outbound transfer. Analyst pulls corresponding packet capture to confirm exfiltration of customer database records. Incident response can see exactly what tables, columns, rows got compromised even though firewall only saw encrypted flows.

  • Threat intel warns of command and control phone home by advanced attacker. Security engineer feeds IOCs into Arkime to scan historical packets finding malware beacon traffic to remote server – indicating attacker pivoted from initial access point months ago! Saved PCAP files provide definitive proof no encryption or obfuscation was used.

For regulated sectors like financial services and healthcare, Arkime offers an enterprise scale "network black box" readily making forensic data available to multiple teams on demand.

Head to Head Comparison

With so many capable tools, it helps narrowing down the field against specialized requirements. Here is high level look at how the packet analysis solutions stack up across crucial considerations:

Capsa TCPDump PRTG Wireshark Arkime
Open source No Yes No Yes Yes
Cloud support On Prem Both Both On Prem Both
Anomaly detection Yes Plugins Add-on Plugins Yes
Scalable retention Months Manual archive Weeks Manual 10s years
Concurrent flows Millions 100Ks 100Ks 10Ks Billions
Encryption AES-256 No Transport No AES-GCM-256
Protocols detected 1800+ 1000s (extensible) 1000+ 3000+ 1000s
Path reconstruction Yes No Partial Yes Yes
Application dependency maps Yes No Yes No No
Prescriptive diagnostics Yes No For devices No No
User activity linking Yes Manual enrichment For devices Manual Yes
Learning curve Low High Low High Medium

Recommendation by Use Case:

Network Engineering – For baseline monitoring, diagnostics and capacity planning choose Capsa or PRTG. Both provide dashboards surfacing utilization stats tied to user experience.

Application Performance – Tracing transaction latencies and errors benefiting apps choose Capsa or Wireshark. The decoding and flow details isolate culprit devices or code paths.

Compliance and Audit – Showcasing protocol enforcement and data governance leverage Arkime or Capsa. Long term retains meeting mandates plus encryption keeps data secured.

Incident Response – Reconstructing post-breach narratives to confirm impact taps Wireshark and Arkime. Tables detail exfiltration content with custom decoders illuminating obscured channels.

Small Team Getting Started – Solo analysts or small shop IT generalists gain wins fast with Capsa or PRTG. Avoid the complex tinkering trading ease of use for power and flexibility.

Expert Guidance Making the Most of Packet Analysis

Now that we have weighed some leading options, let‘s wrap with 5 key guidelines to ensure your packet capture initiatives extract maximum security and operational value from the wires:

  1. Start passively without disruption – Initially configure optical splitter for link aggregation or enable port spanning on switches copying traffic to your sensors. Want packet capture impact to be invisible to users as you baseline network patterns.

  2. Set packet size correctly – Size matters! Check your network MTU norms so sensors snapshot full packet details rather than fragments. Often 1500 bytes works well.

  3. Filter strategically – Storage and analytics scale better when capturing just traffic essential for planned use case. Exclude known backup streams, expected device multicast if able.

  4. Anonymize data early – Before lengthy retention explore scrambling or masking personal user details that may show up in packets. Meet data privacy regulations like CCPA and GDPR.

  5. Enrich with metadata via policy – Your systems populate details on users, devices, applications. Burn matching identifiers into traffic feeds so later can pivot across this context.

Leveraging even a small packet capture trial following these tips will showcase immense value before expanding monitoring and security coverage more broadly across infrastructure.


This comprehensive guide breaks down "must know" packet capture and analysis fundamentals – while contrasting capabilities of 5 popular tools:

Colasoft Capsa – Integrated analysis and diagnostics efficiently addressing small to very large enterprises

TCPDump – Open source packet inspection staple from Linux/Unix CLI

Paessler PRTG – Unified infrastructure and network monitoring with solid packet support

Wireshark – Expert standard driving advanced troubleshooting workflows across industry

Arkime – Scales to tap enterprise fire hose traffic levels while enriching monitoring and threat hunting security routines

We hope mapping options against use cases and exposing expert guidance gives you the 360 degree visibility to navigate packet analysis confidently. Please share feedback on which solution you pick and lessons learned getting value from network packets!