NW Kings

JANUARY 7, 2025

In this blog, we will explore what static routes are, how they differ from dynamic routes, and how to configure them on routers like Cisco devices. This characteristic makes them efficient for routers with limited processing capabilities. A static route is a manually configured path in a routing table.

Routers 52

Routers IP Address Protocol Topology 52

Kentik

MAY 8, 2023

While redundancy is a significant contributor to network resilience, other mechanisms, protocols, and methods can also contribute to overall network resilience. Many network protocols have been designed to handle different aspects of this process. Many network protocols have been designed to handle different aspects of this process.

Network 52

Network Networking IP Address TCP 52

Kentik

MAY 21, 2019

The Mirai botnet was first discovered back in 2016, but has continued to persist and abuse common vulnerabilities and exposures (CVEs) on IoT devices, including home routers and many other network-connected devices. These addresses were apparently port scanning IP addresses that belonged to the company sending the letter.

Port 81

Port IP Address Internet Network 81

CloudFaire

JANUARY 3, 2025

As a result, Internet devices usually use a single path and let the routers handle the path selection. It's a major extension to the TCP protocol, and historically most of the TCP changes failed to gain traction. This is configured with ip mptcp endpoint. subflow , like: $ ip mptcp endpoint add dev wlp1s0 192.0.2.3

TCP 137

TCP Port Server Advertising 137

CATO Networks

APRIL 26, 2016

It lies at the core of how the Internet was built, its protocols, and how service providers implemented their routing layer. There isnt going to be a shiny new router that would magically solve it all. If they are lost along the way, it is the responsibility of higher-level protocols such as TCP to recover them.

Internet 52

Internet Routers MPLS Protocol 52

Kentik

OCTOBER 12, 2021

When companies started outsourcing the hosting of their websites to the likes of Akamai and AWS, network teams learned quickly that many work- and non-work related applications shared the same IP address. These protocols helped the NPM identify applications. It looks like DNS is heading in the HTTPS direction as well.

Encryption 84

Encryption DNS IP Address Protocol 84

Kentik

FEBRUARY 8, 2016

Designed before the dawn of the commercial Internet, the Border Gateway Protocol (BGP) is a policy-based routing protocol that has long been an established part of the Internet infrastructure. An internal routing scheme so that every router in a given AS knows how to get to every other router and destination within the same AS.

Advertising 49

Advertising Routers Internet Protocol 49

Kentik

FEBRUARY 8, 2023

Port mirroring Another method for gathering traffic telemetry is port mirroring, which replicates (mirrors) the network traffic on a switch or router to a monitoring device. Then, correlate that data with information such as IP addresses, MAC addresses, and device names.

Network 111

Network Networking Port IP Address 111

Kentik

MARCH 13, 2019

A common DDoS mitigation technique is Remotely-Triggered Black Hole (RTBH), which requires extensive pre-configuration of discard routes and/or uRPF on all edge routers. For destination-based RTBH, the victim’s destination IP address becomes completely unreachable. IP Protocol. Destination Prefix. Source Prefix.

IP Address 49

IP Address Port Routers DNS 49

Kentik

JUNE 7, 2023

They capture detailed information about network traffic, including: Source and destination IP addresses Ports Protocols Packet counts By analyzing these logs, you can gain visibility into the volume, patterns, and characteristics of traffic, such as whether it’s being dropped or incorrectly routed, to identify connectivity issues.

Cloud 97

Cloud Gateway Port IP Address 97

Kentik

AUGUST 14, 2017

We know that flows are a set of packets that share common attributes including protocol, source and destination IP, and src, dst, and next-hop AS. are generated by individual routers, switches, and hosts rather than system wide. Base the rule on IP, which might be stated as “if IP address is in subnet 123.456.78.90

IP Address 40

IP Address Routers Network Networking 40

Kentik

AUGUST 1, 2016

In particular we’ve learned that speaking or advertising BGP to your service providers and/or peers lets you do two things: Make semi-intelligent routing decisions concerning the best path for a particular route to take outbound from your network (otherwise you would simply set a default route from your border routers into your service providers).

Routers 40

Routers Advertising IP Address Ethernet 40

Kentik

JULY 20, 2018

NetFlow is a protocol that was originally developed by Cisco to help network operators gain a better understanding of their network traffic conditions. Juniper MX and PTX series routers (via IPFIX). Alcatel-Lucent routers. Huawei routers. Cisco Catalyst switches. Enterasys switches. Flowmon probes. Linux devices.

Routers 40

Routers IP Address Protocol Server 40

Kentik

APRIL 18, 2016

While NetFlow v9 and it’s follow-on protocol IPFIX offer tremendous flexibility there are some tradeoffs including complexity of implementation and the fact that a template must be received before the underlying flow data records can be correctly understood. The sFlow difference.

Protocol 40

Protocol Routers Encryption IP Address 40

Kentik

MARCH 28, 2016

How flow protocols adapt as network needs evolve. But while NetFlow and its variants like IPFIX and sFlow are similar overall, beneath the surface there are significant differences in the way the protocols are structured, how they operate, and the types of information they can provide. More of a good thing.

Protocol 40

Protocol Routers MPLS IP Address 40

CATO Networks

JANUARY 17, 2018

The University of Pennsylvania, for example, uses network scanning in the study of global trends in protocol security. However, while research projects will stop at scanning Internet IP-ranges for potentially open services, malicious actors will go further and attempt to hack or even gain root privilege on remote devices.

Network 52

Network Networking Server Port 52

Kentik

OCTOBER 20, 2021

We can’t telnet to the routers in the path because different companies in different countries own them. Using BGP, public IP addresses can be associated with a business’s Autonomous System, but this doesn’t always reveal the actual application (e.g., How then can we gain visibility into why a connection is slow for a given user?

Encryption 52

Encryption Routers DevOps Application 52

Kentik

APRIL 24, 2017

Comparing flow protocols for real-world large-scale networks. A lot of ink has been spilled over the years on the topic of flow protocols, specifically how they work and their relative accuracy. One of the things that can be rather confusing is that there are a lot of different flow protocol names.

Protocol 40

Protocol Routers Bandwidth Internet 40

Kentik

APRIL 3, 2023

You can modify the program to capture other information as well, such as the number of retransmit attempts or the source and destination IP addresses of the affected packets. Second, in a busy network, devices such as routers, switches, and firewalls may be very busy operating at a relatively high CPU.

TCP 110

TCP Application Virtual machine Network 110

Kentik

APRIL 25, 2016

Note that in this and all following examples, all identifying information (IP addresses, router names, AS names and numbers, subnets, etc.) In this example we chose to count the “protocol” column because it’s the narrowest field (1 byte) and provides the best performance for COUNT(). What about counting bytes and packets?

Engineering 40

Engineering Routers Protocol IP Address 40

Kentik

DECEMBER 2, 2015

Here’s how these types of schemes work: The spammer sends a SYN from a spoofed source IP address to TCP port 25 (SMTP) on the target mail server. AND protocol = 6. The WHERE conditions involve protocol 47 this time instead of TCP source port 25. Note: Here at Kentik, we’re big fans of BCP-38 (a.k.a. anti-spoofing, a.k.a.

TCP 40

TCP Protocol Port IP Address 40

CATO Networks

APRIL 19, 2017

Easy and Rapid Configuration For years, WAN engineering has meant learning CLIs and scripts, mastering protocols like BGP, OSPF, PBR, and more. SD-WANs start to address some of these challenges by segmenting the WAN at layer three (actually, layer 3.5, It was an arcane art and CCIEs were the master craftsman of the trade.

WAN 40

WAN MPLS Wide Area Network Firewall 40

Kentik

MARCH 6, 2017

The Akamai report identifies these top infrastructure attack vectors as UDP fragmentation, Domain Name Service (DNS) reflection, and Network Time Protocol (NTP) reflection. These limits cause suboptimal detection due to: Monitoring ranges of IP addresses rather than individual IPs.

IoT 40

IoT DNS IP Address Server 40

Kentik

MARCH 6, 2019

Jaguar (OpenDaylight) - provides overlay network with one IP address per pod. Kube-router (CloudNativeLabs) - provides a Linux LVS/IPVS-based service proxy, a Linux kernel forwarding-based pod-to-pod networking solution with no overlays. Knitter (ZTE) - provides the ability of tenant management and network management.

Network 63

Network Networking Application Cloud 63

Kentik

JUNE 5, 2023

A mis-origination occurs when an AS originates (announces with its ASN as the origin) a new advertisement of a route to an IP address block over which it does not possess legitimate control, consequently soliciting traffic destined to those IP addresses.

IP Address 145

IP Address DNS Internet Routers 145

Kentik

JULY 28, 2021

Latency : Missing packets in connection-oriented protocols such as TCP and QUIC result in lost packets getting resent. Bad hardware (the switch or router port). Overwhelmed router. Congestion in the form of high-connection utilization or an overworked router in the path is another common source of trouble. UDP vs. TCP.

Cloud 116

Cloud TCP Routers Protocol 116

Kentik

APRIL 24, 2021

By comparison, AS8003 now announces 61 million more IP addresses than the now-second biggest AS in the world, China Telecom, and over 100 million more addresses than Comcast , the largest residential internet provider in the U.S. Over the years, only a portion of that address space was ever utilized (i.e.

Internet 145

Internet IP Address Protocol Advertising 145