Security criteria for selecting a network switch?
I am looking to purchase a switch with 24+ ports. The set of security criteria that I should bear in mind when selecting a switch is not clear to me. I have tried to take other networking security...
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Why are ethernet ports always upside-down?
I have noticed that in almost every board, RJ-45 Ethernet sockets are always soldered upside-down. Why are these sockets made this way? Wouldn’t it be easier to make and solder them with the pins...
View ArticleHow to ensure security between devices from different manufacturers over...
I’m involved in the design of a protocol that allows different manufacturers to share data amongst their products. The protocol uses multicast over Ethernet so any device can join. Note that it’s very...
View ArticleEthernet easyWeb lpc17xx [on hold]
I have seen that MCB1700 which comes along with keil has an easyWeb application for ethernet(C:KeilARMBoardsKeilMCB1700EasyWEB). The problem is that there any no documents available to understand the...
View ArticleCan the fake USB flash drive attack happen over Ethernet?
You may have seen the article This USB Drive Can Nuke A Computer where it shows how a flash drive shaped device can completely fry out all the components of a computer. This is very shocking (pun...
View ArticleOscillator and output load
For the Ethernet application in my design using RMII interface, I need to drive two CMOS loads (two reference clock pins, one of a Freescale Kinetis K60 Microcontroller and one of a TI’s PHY chip)...
View Articlecheck tcp packets reception below tcpdump level
I am having an issue with my smartphone device and packets monitoring: I am trying to find a reason why I cannot establish a VPN connection via PPTP protocol. I have the following successful scenario:...
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Ethernet PHY Device read and write operation is not working
I am trying to Read and write the DM9161A PHY MII-register through EMAC ATSAM3x8e. phy_mii_write() { //set the phy maintain register (SOF=01;RW=01;PHYADDR=0x01;REGADDR=0x00;CODE=10;DATA=00C) //...
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Vcc pin of TVS diode array
Bourns has various TVS diodes to protect Ethernet ports. Most of them (for example CD143A-SR05) have GND, VCC and I/O pins. I/O pins are for Ethernet signal line. Why do these TVS diodes have VCC pin?
View ArticleFCS verification of ethernet frame
i am trying to transmit a Ethernet frame from fpga to pc. my udp frame is: constant udp_frameB :frame60:= (x"FF",x"FF",x"FF",x"FF", -- mac dest x"FF",x"FF",x"00",x"00", x"00",x"04",x"14",x"13", -- mac...
View ArticleHow to test Ethernet PHY's MDI interface through JTAG Boundary scan
We now use SCANWORKS Boundary Scan Tool from ASSET to make Ethernet SWITCH’s manufacturing test. But in almost all PHY chips from broadcom corp, the MDI interfaces are “Linkage” bits. It means that...
View ArticleHow do other Macs in the network see my Freenas 9.3 backup drive attached to...
I have a Time Machine back up setup on a Freenas 9.3 server. It works really slowly via WiFi attached to my broadband router. So, I attached it directly to my iMac via Ethernet instead – a full backup...
View ArticleEthernet Signals Complementary
I’m doing a little project, regarding a ethernet to fo converter but I have some doubts. The problem is how TX+ and TX- behaves, are those complementary? I mean if TX+ is high than TX- is low. My other...
View ArticleTwo networking interfaces trying to get an IP via DHCP
When using: /etc/network/interfaces auto lo iface lo inet loopback auto eth0 iface eth0 inet dhcp auto wlan0 allow-hotplug wlan0 iface wlan0 inet dhcp wpa-ssid "<myssid>" wpa-psk...
View ArticleCannot connect to LAN with USB Ethernet adapter
I had bought a Giga LAN USB 3.0 ethernet adapter for my new 12″ MacBook. I just installed the driver required but the MacBook does not recognize the adapter (showing no ethernet connected) and can’t...
View ArticleAirport extreme seems to place a limit on gigabit ethernet
I have a gigabit internet which goes into my airport extreme. Everything is working fine now except the fact that the Gigabit Ethernet port has a limit of 200mb/s when tested. If I plug the main...
View ArticleReceiving sensor data with Arduino: push or pull?
Every second I am reading a data string (comma-separated) from a battery management system via RS232. The first step was stripping the field name from the value; at times resulting in skipping a beat....
View ArticleSingle cable for dual Ethernet plus power (PoE)
I would like to run two 100 Mbit Ethernets including a common PoE over a single cable which will be about 3-5m long. Since 100 Mbit needs 4 wires I will need 8 plus some wires for the PoE which is at...
View ArticleDelay after a MAC change
I am writing a script that will change my ethernet MAC address on a local network. It will work as follows: Initially eth0 will be brought down MAC will be changed using the ifconfig utility eth0 will...
View ArticleiTunes downloading movie faster over WiFi
For some reason iTunes will download a movie faster over wifi than with ethernet on my home network. When I do a speed test the ethernet connection appears to be a few mbps faster though… Why would it...
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