Kentik

JANUARY 24, 2022

Back in the 1990s, NetFlow was introduced on Cisco routers as a means to collect information about IP network traffic as it enters or exits an interface. Since then, network flows have been one of the best ways to gain insight into traffic. Source IP address. Destination IP address.

Application 96

Application IP Address DNS Port 96

DoorDash Engineering

NOVEMBER 29, 2022

As DoorDash’s business grows, engineers strive for a better network infrastructure to ensure more third-party services could be integrated into our system while keeping data securely transmitted. The following sections will discuss how our team established network connections with such vendors.

Data Centers 97

Data Centers Cloud Gateway IP Address 97

Kentik

SEPTEMBER 20, 2021

Latency is not a new problem in networking. Not as difficult as time travel, but it’s difficult enough so that for 30+ years IT professionals have tried to skirt the issue by adding more bandwidth between locations or by rolling out faster routers and switches. Fast forward to today, most networks enjoy five nines (99.999%) of uptime.

TCP 116

TCP Routers Bandwidth IP Address 116

Kentik

FEBRUARY 8, 2023

Traffic telemetry is the data collected from network devices and used for analysis. As a critical input to a network observability platform, this data can help monitor and optimize network performance, troubleshoot issues, and detect security threats. Monitoring network traffic can be expensive.

Network 111

Network Networking Port IP Address 111

Network Engineering

MAY 5, 2023

I have this network when the network tries to communicate with the routers it fails. Router>enable Router# Router#configure terminal Enter configuration commands, one per line. Router(config)#interface GigabitEthernet0/0 Router(config-if)#ip address 172.17.2.1 End with CNTL/Z.

IP Address 52

IP Address Routers Protocol Network 52

Kentik

OCTOBER 4, 2021

According to a statement published last night, Facebook Engineering wrote, “Configuration changes on the backbone routers that coordinate network traffic between our data centers caused issues that interrupted this communication.” tfbnw.net — which is another router inside AS32934 that belongs to Facebook. So what happened?

TCP 145

TCP DNS Server Media 145

Network Engineering

JANUARY 14, 2025

If I assign a static IP on the device level that is within the DHCP range of the network it's on, but don't reserve its address on the DHCP server, will the device lose its IP address or be disconnected if the router restarts?

IP Address 52

IP Address Routers Server Network 52

Kentik

MAY 8, 2023

Core Concepts Resilience in networking is the ability of a network to withstand and quickly recover from failures or changes in its environment. This includes the ability to: Dynamically adjust to changes in network topology Detect and respond to outages Route around faults in order to maintain connectivity and service levels.

Network 52

Network Networking IP Address TCP 52

Kentik

JANUARY 10, 2022

Or, perhaps one or more of the 10-20 routers in the path needed to reach the destination gets busy for a hundred milliseconds or so. Domain lookup time : When a connection is made to a domain, the local operating system must first reach out to the DNS to resolve that hostname to an IP address. Where is the DNS?

IP Address 98

IP Address DNS TCP Application 98

The Network DNA

JULY 5, 2024

Introduction to VXLAN MP-BGP EVPN Route Types Before we start with the route types lets talk about the EVPN, EVPN (Ethernet Virtual Private Network), enables virtualized Ethernet communication between various network devices. It operates by using IP plus UDP to travel over the physical network.

IP Address 52

IP Address Ethernet Advertising Unicast 52

CloudFaire

JANUARY 3, 2025

As a result, Internet devices usually use a single path and let the routers handle the path selection. MPTCP aspirations Being able to separate the lifetime of a connection from the lifetime of a flow allows MPTCP to address two problems present in classical TCP: aggregation and mobility. This is configured with ip mptcp endpoint.

TCP 137

TCP Port Server Advertising 137

The Network DNA

JULY 9, 2024

Replacing cEdge in Cisco SDWAN environment Replacing the cEdge router with another cEdge through an RMA process for Cisco SDWAN , we need to put the basic configuration on the new RMA router and should be reachable via vManage. It is important that you should know the new router serial number should be learned to vManage NMS.

Routers 52

Routers IP Address MPLS WAN 52

NW Kings

JANUARY 7, 2025

Static routes are fundamental components in networking that help direct traffic efficiently from one network segment to another. 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. What is the role of static routes in networking?

Routers 52

Routers IP Address Protocol Topology 52

CATO Networks

FEBRUARY 22, 2022

However, global changes like remote work, mobile connectivity and cloud-based infrastructure require businesses to reconsider their MPLS network strategy. MPLS (Multiprotocol Label Switching) is a network routing technique that is based on predetermined paths, instead of routers determining the next hop in real-time.

MPLS 52

MPLS Routers Network Networking 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

Network Engineering

FEBRUARY 2, 2024

set system mode router ! vlan database vlan 10,20 exit interface vlan 1 ip address 101.205.25.252 255.255.255.0 no ip address dhcp ! interface vlan 10 ip address 101.205.10.1 interface vlan 20 ip address 101.205.20.1 255.255.255.0 ! 255.255.255.0 !

IP Address 52

IP Address Port Routers 52

Network Engineering

AUGUST 19, 2020

The problem is that when ESXi is down it takes down all the network with it, so I have to boot up another router to log in to it. edit1: This is a mockup of current/future network. ip dhcp pool mgmt network 10.0.0.0 default-router 10.0.0.1 domain-name LAN ip dhcp pool trusted network 10.0.10.0

IP Address 52

IP Address DNS Routers Server 52

Network Engineering

JULY 19, 2021

Here are my config to this network. I would really appreciate ISP Int g0/0 ip add 2.2.1.1 255.255.255.252 no shut Int g0/1 IP add 2.2.2.1 255.255.255.252 no shut int g0/2 ip add 2.2.3.1 255.255.255.252 no shut int g0/3 ip add 4.4.129.1 255.255.255.252 no shut int g0/3 ip add 4.4.128.1 or later ! 2.2.1.1 !

IP Address 52

IP Address Encryption Routers Network 52

Kentik

APRIL 6, 2021

Flow logs are generated only from VPCs, subnets, and network interfaces. Private subnets are useful in transit hub architectures as these are great places for cloud and network operations teams to place bastion hosts and other shared services that need to be in the center of the action. Lastly, attach an internet gateway to the VPC.

Gateway 98

Gateway Cloud Network Networking 98

Kentik

JUNE 7, 2023

Enterprises migrate to multi-cloud networks not because they want to, but because they have to. Two exciting new capabilities help you quickly answer any question about your multi-cloud network: Kentik Cloud users can now collect, analyze, and visualize flow logs generated on AWS Transit Gateways. There’s an acquisition.

Cloud 97

Cloud Gateway Port IP Address 97

Kentik

SEPTEMBER 19, 2018

Let’s face it — today’s networks are complex. The physical topology continues to expand with relentless traffic growth, and a constant stream of new technologies like SDN, Clos architectures, and cloud interconnects make it even harder to understand how services traverse the network between application infrastructure and users or customers.

Network 49

Network Networking Routers Server 49

NW Kings

JANUARY 25, 2025

In today’s digital landscape, mastering Python for Network Engineers is essential for automating tasks and improving efficiency. This blog will take you through the key concepts and practical exercises that will enhance your skills in Python programming tailored for networking professionals.

Engineering 52

Engineering Network Networking IP Address 52

Kentik

DECEMBER 13, 2021

Notice above that the routers used in the connection are looking pretty snappy. If you “ain’t afraid of getting dirty,” use the Wireshark packet analyzer to see if your connection to the SaaS applications’ IP address is suffering from any packet loss. Check your local network. The problem may not be yours to solve.

Application 95

Application DNS Routers Server 95

Network Engineering

JANUARY 31, 2025

After a juniper router upgrade we started having MTU problems. I'm no longer able to send the router a 1500 byte ICMP packet (on a direct attached subnet with vlan) and get a reply. So, I never needed this config before, nor do I need it in other parts of the network, but it's a mystery to me where these extra 4 bytes are coming from.

Routers 52

Routers IP Address Server Network 52

DoorDash Engineering

JANUARY 16, 2024

Internal Envoy routers allow communication between the global cell and replicated cells. Direct communication in a flat network: Leveraging AWS-CNI , microservice pods in distinct clusters within a cell can communicate directly with each other. Clients leverage DNS names to dynamically discover all pod IP addresses of desired services.

Cloud 84

Cloud IP Address DNS Routers 84

Kentik

MARCH 6, 2019

Understanding the network footprint of applications and services is now essential for delivering fast and reliable services in cloud-native environments. Networking is not evaporating into the cloud but instead has become a critical component that underpins every part of modern application architecture. A Refresh: Kubernetes Basics.

Network 63

Network Networking Application Cloud 63

The Network DNA

NOVEMBER 26, 2024

Cisco ASA in a Network Configuring DHCP, AAA, and SSH NDNA-ASA(config)# dhcpd address 10.10.10.3-10.10.10.100 NDNA-ASA(config)# dhcpd option 3 ip 10.10.10.1 Configure address translation using PAT and network objects NDNA-ASA(config)# object network INSIDE-NET NDNA-ASA(config-network-object)# subnet 10.10.10.0

Firewall 52

Firewall IP Address VPN Port 52

Kentik

SEPTEMBER 10, 2021

If the response comes back like the above, I’ll probably reboot my computer, my internet router or maybe both and hope that this fixes the problem. And which router or autonomous system introduced the latency? In the picture above, by mousing over the little green circles at the bottom, the IP address of the hops are listed.

Application 113

Application Cloud Routers IP Address 113

Kentik

MARCH 13, 2019

With many attacks stemming from totally unpredictable events like political dissent, employee misconduct, or actions of third parties, every type of organization needs to be prepared to mitigate DDoS attacks and proactively defend their networks to ensure business continuity. Which Network Vendors Support Flowspec? Action Type.

IP Address 49

IP Address Port Routers DNS 49

The Network DNA

MAY 24, 2024

This policy will match with the site id and we use this policy for the router in Site-1 only towards outbound direction. In order to manipulate the traffic from the DC-1 to Site-1 you need to apply the policy on DC-1 router using the data policy and import it to the Centralized policy. Continue Reading. x Free Tools.

MPLS 52

MPLS WAN IP Address Routers 52

The Network DNA

NOVEMBER 26, 2024

Cisco ASA Firewall in a Network What is Cisco ASA Firewall? Cisco ASA is a security device that includes a firewall, antivirus, intrusion prevention, and a virtual private network (VPN). It enables proactive threat defense, preventing assaults from spreading throughout the network. NDNA-ASA(config-if)# ip address 112.23.16.11

Firewall 52

Firewall VPN IP Address Port 52

Kentik

APRIL 3, 2023

Those calls could be for kernel services, network services, accessing the file system, and so on. Therefore, by looking at the interactions between the application and the kernel, we can learn almost everything we want to know about application performance, including local network activity. How does eBPF work?

TCP 110

TCP Application Virtual machine Network 110

CATO Networks

JANUARY 17, 2018

In the light of recent ransomware attack campaigns against Microsoft RDP servers, Cato Research assessed the risk network scanning poses to organizations. What is Network Scanning? Network scanning is a process for identifying active hosts on a network. Whats Services Are Normally Targeted By Network Scanning?

Network 52

Network Networking Server Port 52

Kentik

OCTOBER 12, 2021

It’s interesting to observe how encryption and network performance monitoring (NPM) have evolved over time. When I first entered the networking industry right out of college, many applications sent passwords over the network in clear text, unencrypted. Since just about everyone’s PC was wired back to a repeater (i.e.,

Encryption 84

Encryption DNS IP Address Protocol 84

Kentik

JUNE 21, 2021

The end result is complex and often brittle networking environments, and cloud professionals are left in the dark. For AWS cloud networks, the Transit Gateway provides a way to route traffic to and from VPCs, regions, VPNs, Direct Connect, SD-WANs, etc. Transit Gateways are also fundamental for global cloud and hybrid networking.

Gateway 82

Gateway Cloud VPN IP Address 82

Kentik

FEBRUARY 8, 2016

For reasons of enforced obfuscation by RFC writers, routes are also called Network Layer Reachability Information (NLRI). Another foundational concept is the Autonomous System (AS), which is a way of referring to a network. That network could be yours, or belong to any other enterprise, service provider, or nerd with her own network.

Advertising 49

Advertising Routers Internet Protocol 49

CATO Networks

APRIL 26, 2016

There isnt going to be a shiny new router that would magically solve it all. IP Routings Historical Baggage: Simplistic Data Plane Whether the traffic is voice, video, HTTP, or email, the Internet is made of IP packets. Packets hop from router to router, only aware of their next hop and their ultimate destination.

Internet 52

Internet Routers MPLS Protocol 52