In this link you can check the comparison of both devices :
I had the same question. After looking at the comparison chart listed in the reply below, it appears that the 350 has an external, laptop-type brick power supply and the 355 has an internal power supply that takes a regular IEC power cord. I haven't ever seen these devices IRL or even pictures of the back to compare, *but* the 355 is listed as 2.6 lbs heavier and a bit deeper too, I think.
That is my best educated guess from what I derived from the specs on paper & many years of dealing with rack gear Maybe someone who has seen them firsthand can confirm.
I had long forgotten about this thread, but we ended up buying one to find out and my organisation have started using SG355 switches in place of SG350-10P. Certainly the PSU is internal and it takes a regular IEC.
We use the same config as used on SG350, I am fairly confident (but cannot be 100% certain) that they are the same switch internals just with a different PSU and chassis. Hope that helps!
Welp, I haven't ripped into the guts of these things to compare /contrast but I have been poring over spec sheets, comparison charts and pictures. Based on that, not-so-firsthand evidence I would venture to say they are functionally the same and likely the same internals. Only makes sense with economies of scale and all that. Although, having said that I'm confused as to why the SG355 exists at all. I mean, why go to the trouble to make a small switch in these two versions?
That was rhetorical, but let me just go for it and speculate. Perhaps there was a critical mass in this market segment where that particular configuration was attractive and hit a sort of sweet-spot where there were some people who were implementing it as a desktop or shelved solution but there was still enough demand for people wanting a regular 1U *real* rack version with an internal PSU and a wide chassis, not just the funky extendo-rack ears.
I've probably been up for too many hours soaking up (err... doing my best to soak up) various elements of networking as I've been cramming Crestron multicast video specifics, dante audio specifics and just general tcp/ip model <-> OSI model networking stuff to a degree that I haven't since the mid-90's (I'm not really a 'real' network guy) but I get into these rabbit-holes where I think (obsess?) about why certain platypuses exist in the wild. I love the exploration of the chicken (the chinese chicken) and the egg... like how nothing is created in a vacuum and sometimes the strangest things get produced and catch unexpected attention-focus. (there are some Crestron cart-based systems like that right now cuz of COVID-1). There has to be some demand or financial incentive. Let's face it: follow the money is (nearly) always true. Whether we're talking Edison vs Tesla, Betamax vs VHS, HD-DVD vs Blu-Ray, etc. its not always clear which forces will combine to allow something to exist or even dominate a particular market at a particular time.
I digress, I know, but there haven't been other cases like this have there? I mean in the recent model matrix... no other lil 8-10port desktop switch that ends up with a true rack version? Or maybe I'm being short-sighted and in a crossover-point like small-business <-> enterprise or consumer<-> pro this kinda thing happens more often than I realize. Hmmmm....
I actually just bought a SG350-10P and it seems to sit in the sweet spot for my current needs. I often find myself ahead of the curve just enough that the feature set I'm seeking in a product just isn't there yet and I struggle with frustrating 'almost-but-no-cigars' and 'close-but-not-quite' implementations for ~6 months to a year or so before moving on to some other project or area of interest. Then I turn around in another ~6-9 months and someone I know is playing with the evolved, market-ready version of what I was tinkering with, toiling to make work how I wanted it to, how it *should* work... and they extol all the virtues and explain how awesome and life-changing their new, favored product is... and every.single.time i'm like dammit! if only I hadn't NEEDED to do that like a year to 18-months ago things coulda been so simple!
I've been there with USB-audio devices, interconnecting various older HW-based & newer software-based video conferencing products, integrating analog and digital audio... audio mostly but AV in general.. so anyway I'm thankful to have found this little switch for my tinkering right now. It meets my needs for a Layer 3, fully manageable gigabit switch that I can tweak multicast, IGMP snooping, querier settings, power devices with PoE af & at, turn off the annoying (for dante) EEE energy savings settings, create VLANs, manage QoS and configure it so my Crestron NVXes get full throughput.
I haven't had time to wail on this stuff exhaustively yet, but so far, so good! I will do some multi-switch configs once the SG300-10 I scored on last night arrives. As I mentioned at length earlier in this post, I'm not used to being on this side of things... where they're mostly working as I need w/o much re-engineering from the ground up. So yea, I can see why this lil switch is a package that would be attractive enough for various applications to merit two incarnations: a real rack unit and a portable/desktop version.
If anyone knows of gotchas or inconsistencies/idiosyncrasies of either of the SG350-10P , the SG300-10 or weirdness that results from working with the combo, please give me a head's up. I'm thinking since they run different firmware versions maybe there will be some weird versioning implementation differences between the two.... like IGMP or QoS, etc. I mean, hey if it's all just SMOOTH that'd be great, but I'm a bit too cynical to buy into that fairy tale just yet.
Sheesh! I dunno if any of that is comprehensible at all or just the ravings of a sleep-deprived madman but I need to get some sleep right about NOW. Late!