silenteh

May I ask if you run a distributed filesystem on top of ZFS and if so which one ?

Zurich Switzerland - REMOTE

Freelancer with more than 15 years of experience.

Recent work:

- Developed a Java service which saves 50% of costs to an Amazon EC2 customer: Java + Netty

- Developed a advertising server which handles over 50 billion impressions per month: Java + Netty

- Developed a statistics collector which records over 50 billion impressions per month: Scala + Netty + Akka + HDFS

- Writing Golang code for over two years

- DevOps role: created several continuous integration and deployment pipelines.

- Over 10 years of Linux administration

- Several blockchain projects

Email in the profile.

Sebastian

SEEKING WORK - Zurich Switzerland - REMOTE

Freelancer with more than 15 years of experience.

Recent work:

- Developed a Java service which saves 50% of costs to an Amazon EC2 customer: Java + Netty

- Developed a advertising server which handles over 50 billion impressions per month: Java + Netty

- Developed a statistics collector which records over 50 billion impressions per month: Scala + Netty + Akka + HDFS

- Writing Golang code for over two years

- DevOps role: created several continuous integration and deployment pipelines.

- Over 10 years of Linux management

I prefer long term projects.

Email in the profile.

Sebastian

If you are looking for a free book about applied cryptography, in my opinion this is the best you can find:

https://crypto.stanford.edu/~dabo/cryptobook/

Here a nice explanation of the vulnerability: https://blog.exodusintel.com/2016/02/10/firewall-hacking/

There is also a Snort signature to detect attempts to exploit this vulnerability.

I am still downloading the library, just to take a quick look at it, however 254MB seems a bit oversized...

You are right, I should have probably mentioned I am doing it on my free time and no one is paying me. It's just pure curiosity. :)

Why would I not ?

This brought me to dig deeper into Elasticsearch code, find out more about its code quality, deal with machine endiannes, deal with byte shifting, think how to structure code in Golang and overall enjoy the feeling of touching the bare metal again...

The clients actually acts as a cluster node and therefore has knowledge about the cluster state, its indexes and shards, because it receives notifications from it, once it joins.

This allows to execute operations on a specific shard of a specific index on a specific node of the cluster resulting in better performance than going through the HTTP interface.

It can be used to efficiently store big quantities of data, for instance logs, which then can be visualized with Kibana.

It's just unfortunate that Elasticsearch presents the problems mentioned in the article and which I also experience in production, because it has a series of plugins which makes it a good solution for specific use cases.

I am currently writing a Golang client for Elasticsearch which uses the native binary protocol and I have to say the lack of documentation about it is making the process really painful!

I tried to use the Elasticsearch thrift plugin but unfortunately it does not work for the version 1.1 and 1.2

So basically I have to inspect each and every byte of each and every request and response in order to be able to send or parse data.

While developing the client a managed several time to crash the Elasticsearch server by sending malformed packets. In addition, this, brought me to review the networking part of Elasticsearch code and I think it needs a refactoring and a better, deeper and cleaner usage of Netty.

I hope they will soon sort out this and the problems mentioned in the article, since I think that Elasticsearch is really an amazing product!

Location: Switzerland - Remote

Stack: Golang, Scala, Java, Netty, Akka, Cassandra, ElasticSearch, Redis, Reactive

Resume: https://github.com/silenteh/cv/blob/master/silenteh_resume.p...

Contact: HN_USERNAME@gmail.com

Looking for a company where code simplicity and performance matter! I do not like to waste CPUs cycles, memory and I/O in general.

I have more than 13 years experience as a developer and I have been designing and implementing scalable, distributed and resilient systems and software, to handle over 40 million unique users per month, for the last 7 years. I am proficient with Scala, Java, Netty and Akka and I really enjoy coding in Golang. I have a strong passion for cryptography and IT security in general. On my free time, I am working on a Golang Elasticsearch client which uses the tcp transport. I am an open minded, friendly and business driven person who loves technology. So for any questions drop me an email !

Switzerland, Remote, Full Time

Stack: Golang, Scala/Java, Akka, Netty, C, ElasticSearch, NoSQL (Cassandra, MongoDb)

Contact: my HN username at gmail

Resume: please contact me for a copy

In the field for more than 14 years.

I am passionate about cryptography and IT security and I am looking for an opportunity to work on open source projects preferably in crypto and security in general. I have also more than 5 years of experience in scaling web sites and native applications stack with more than 50 billion page views per month. I love talking to others, so for any question feel free to ping me anytime!

Latest books read or in the process of reading:

- High Performance Browser Networking

- Understanding and using C pointers

- Reverse Engineering

The judges who chose AES and SHA-3 as the "winners" of the global competitions are the NSA.

Sure, however this process creates alternatives and if the crypto community thinks the winner is backdoored I am pretty sure we will know it and additionally we will have a valid alternative ready to be implemented. Additionally if the NSA/NIST modifies the specs for the crypto construction there is still the possibility to implement the original one. See SHA-3 for instance. It was about to be weakened, but the crypto community could still implement the original spec.

That would include AES and SHA-3.

You cut the rest of the sentence and therefore changed completely the whole meaning. My original sentence included: "...without going through years of reviews by international cryptographers." Take a look at this video of D.J.B.: https://www.youtube.com/watch?v=G-TM9ubxKIg He makes a great example with the Dual_EC_DRBG, where many cryptographers told NIST that there could be a backdoor. NIST answer basically was: sorry too late, it has already been implemented !

So in other words, in case of Dual_EC_DRBG the standardization process was all in reverse. First NIST standardized it and then the crypto community started to review it and found problems.

In general you should prefer crypto constructions which are a result of global competitions. For example AES and SHA3.

You should avoid at all costs anything that has been standardized by NIST without going through years of reviews by international cryptographers. Dual_EC_DRBG is a clear example of crypto construction which falls into this category.

This is my general rule of thumb.

However knowing which ciphers one should use is not enough! You absolutely need to know HOW to use them. A basic and superficial example is AES in ECB mode, which is semantically secure as long as you use a key to encrypt one and only one single block. Another one is, for example, after how many encrypted blocks a key should be rotated, based on the underlying cipher used.

Once you have learnt how to use the basic building blocks of crypto you are then NOT supposed to write your own implementation and instead use existing ones....there is a small problem with this....they are broken or they either not implement all the necessary crypto constructions you need. OpenSSL is an example of broken crypto implementation, and instead NaCl does not have TLS implemented.

So this is a short summary and my personal opinion of why crypto is hard. On top of all this there are not enough experts out there which have the time to review crypto implementations or new and old constructions, and we are living a historical period where we desperately need crypto to protect our privacy.

So my final suggestions is to take some of your spare time and go through Dan Boneh Crypto 1 at Coursera: https://www.coursera.org/course/crypto

It is worth every single minute.

Once you have done that, I would also suggest you to take the Matasano Crypto challenges: http://www.matasano.com/articles/crypto-challenges/

Finally I want to thank everybody who have taken their time to create and maintain both Crypto 1 course and the Matasano challenges.

You can make a phone call to Apple and they will extend your account for few days if you will explain the situation.

and this is a more recent one http://instagram.com/p/bwS-1Iwr2e/#

This is another example of what pg meant with his last essay.

All non-Apple icons. It looks really weird to me to have some flat icons and some glossy ones.

Unless I am on the first page of the phone, where I normally keep all Apple native apps, it seems to me I have still the old iOS version.

It will probably take some time before I get used to it.

I personally hope the accelerometer-linked 3D will not also help to make flat the battery which already does not last long.

Right, there are different forms of democracies. From this chart I see that US is categorized under Full Democracy: https://en.wikipedia.org/wiki/File:Democracy_Index_2012_gree... https://en.wikipedia.org/wiki/Democracy_Index https://en.wikipedia.org/wiki/Democracy

Unless I am mistaken US and most European countries are based on Democracy. Wikipedia defines Democracy as a form of government in which all eligible citizens have an equal say in the decisions that affect their lives. Granted, wikipedia is not the oracle but it gives a good definition in my opinion. Does, the gathering of my personal data, affect my life ? Well in my personal opinion it does, therefore I should be informed about it.

For anybody interested in learning electronics and hardware design, I suggest this book: http://www.amazon.com/Make-Electronics-Discovery-Charles-Pla...

It really helped me to get into hardware in a structured and clear way.

A must read.

When tcp_tw_reuse is enabled the kernel can decide to use the sockets in TIME_WAIT, before they expire or they are closed by the clients.

This is a problem though, because the connection could still be used by the client and therefore there could be some collisions regarding the TCP sequence numbers, specially on high traffic servers. The kernel can try to avoid this collision with a technique called PAWS (protection against wrapped sequence numbers: rfc1323). Unfortunately PAWS works only with tcp_timestamps enabled on both sides (client and server). tcp_timestamps has also an overhead and therefore it is normally disabled on servers with a high traffic, leading to potential problems.

About tcp_tw_recycle, when it is enabled, it forces the verification of this tcp_timestamp. So in case of NAT, multiple clients will send different tcp timestamp to the server, to the same mapped connection which points to the TIME_WAIT socket, and because the tcp timestamp are different then the packets will be dropped by the kernel. This is the reason why it is not a good thing to enable tcp_tw_recycle when you use a load balancer or in case of NAT.

A good practice is to enable tcp_tw_reuse (instead of tcp_tw_recycle), to make sure tcp_timestamp is enabled and to decrease the size of the tcp timestamp with tcp_timewait_len.

enabling

net.ipv4.tcp_tw_reuse

net.ipv4.tcp_tw_recycle

can create unexpected problems with NAT, so use it with caution.

I think the best way for you to realize the complexity behind it, is to take a look here: - http://www.grc.nasa.gov/WWW/K-12/rocket/shortr.html

With this you are only scratching the surface, so, as you can see, the journey is quite long. If the reading of the above links does not scare you, and instead, it pushes you to learn more, then you are probably on the right path. So learn, apply, fail, rinse and repeat.

You will also realize that electronics is, as well, an important component of a space company, so you will need to learn that too.

Which is in my opinion unfortunate, because this a good way to get to know new startups and to give some constructive feedbacks where possible.

About to launch BagPix: http://bagpix.com

An easy and quick way to share products you have, want or like with your friends, family and the whole world

Additionally I am working on an way to comunicate securely via text messages and phone calls.

The issue with Hetzner is not the price of the servers. The problem is their connection. The max bandwidth I could get was around 180Mb/s, even though their marketing says 1 Gb/s port. In fact the port is shared. I have got around 10 servers there and now I am moving away and decided to go with Amazon. However for a startup with european market it could be a good option.

What about the battery? Any news about it? I really do hope Apple improved it as well!

I would also remove the duplicated content/submissions which create or could create fragmentation of good comments, besides a personal frustration for having just wasted time opening again the same link only because the title seemed different.

This is not necessarily a bad thing for the new startups, in my opinion. I want to quote PG from his essay: The top idea in your mind (my favorite one btw)

{...} I'd noticed startups got way less done when they started raising money, but it was not till we ourselves raised money that I understood why. The problem is not the actual time it takes to meet with investors. The problem is that once you start raising money, raising money becomes the top idea in your mind. That becomes what you think about when you take a shower in the morning. And that means other questions aren't. {...}

This is actually how it works, and more or less always worked here in Europe. No investments, no money raising, only part of your daily job salary invested in your startup ideas, and endless nights learning, coding, failing in a loop....till you succeed and you start to make money.